blocks|key|1714893|text|如果你使用的是.NET+3.5，你可以使用DataTableExtensions.AsEnumerable+(一种扩展方法)，然后如果你真的需要一个List<DataRow>而不仅仅是IEnumerable<DataRow>，你可以调用Enumerable.ToList|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1714894|IEnumerable<DataRow>+sequence+=+dt.AsEnumerable();|code-block|syntax|javascript|1714895|或|1714896|using+System.Linq;
...
List<DataRow>+list+=+dt.AsEnumerable().ToList();|1714897|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/system.data.datatableextensions.asenumerable.aspx|1|http://msdn.microsoft.com/en-us/library/bb342261.aspx^0|L|W|22|D|2K|K|3A|H|L|W|0|3A|H|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]|$9|13|A|14|B|C]|$9|15|A|16|B|C]]|D|@$9|17|A|18|1|19]|$9|1A|A|1B|1|1C]]|E|$]]|$1|F|3|G|5|H|7|1D|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1E|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|1F|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|1G|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]|W|$5|R|S|T|E|$U|X]]]]

If you're using .NET 3.5, you can use <a href="http://msdn.microsoft.com/en-us/library/system.data.datatableextensions.asenumerable.aspx" rel="noreferrer"><code>DataTableExtensions.AsEnumerable</code></a> (an extension method) and then if you really need a <code>List&lt;DataRow&gt;</code> instead of just <code>IEnumerable&lt;DataRow&gt;</code> you can call <a href="http://msdn.microsoft.com/en-us/library/bb342261.aspx" rel="noreferrer"><code>Enumerable.ToList</code></a>:

<pre><code>IEnumerable&lt;DataRow&gt; sequence = dt.AsEnumerable();
</code></pre>

or

<pre><code>using System.Linq;
...
List&lt;DataRow&gt; list = dt.AsEnumerable().ToList();
</code></pre>

blocks|key|1715068|text|List<Employee>+emp+=+new+List<Employee>();

//Maintaining+DataTable+on+ViewState
//For+Demo+only

DataTable+dt+=+ViewState["CurrentEmp"]+as+DataTable;

//read+data+from+DataTable+
//using+lamdaexpression


emp+=+(from+DataRow+row+in+dt.Rows

+++select+new+Employee
+++{
+++++++_FirstName+=+row["FirstName"].ToString(),
+++++++_LastName+=+row["Last_Name"].ToString()

+++}).ToList();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1715069|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>List&lt;Employee&gt; emp = new List&lt;Employee&gt;();

//Maintaining DataTable on ViewState
//For Demo only

DataTable dt = ViewState["CurrentEmp"] as DataTable;

//read data from DataTable 
//using lamdaexpression


emp = (from DataRow row in dt.Rows

 select new Employee
 {
 _FirstName = row["FirstName"].ToString(),
 _LastName = row["Last_Name"].ToString()

 }).ToList();
</code></pre>

blocks|key|1714824|text|使用C#+3.0和System.Data.DataSetExtensions.dll，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1714825|List<DataRow>+rows+=+table.Rows.Cast<DataRow>().ToList();|code-block|syntax|javascript|1714826|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

With C# 3.0 and System.Data.DataSetExtensions.dll,

<pre><code>List&lt;DataRow&gt; rows = table.Rows.Cast&lt;DataRow&gt;().ToList();
</code></pre>

blocks|key|1499734|text|你可以使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1499735|List<DataRow>+list+=+new+List<DataRow>(dt.Select());|code-block|syntax|javascript|1499736|dt.Select()将以datarows数组的形式返回表中的所有行，List构造函数接受该对象数组作为参数，以初始填充列表。|offset|length|style|CODE|1499737|entityMap^0|0|0|0|B|Z|4|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]|$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|N|$]]

You could use 

<pre><code>List&lt;DataRow&gt; list = new List&lt;DataRow&gt;(dt.Select());
</code></pre>

<code>dt.Select()</code> will return all rows in your table, as an array of datarows, and the <code>List</code> constructor accepts that array of objects as an argument to initially fill your list with.

blocks|key|1500291|text|您可以创建扩展函数，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1500292|public+static+List<T>+ToListof<T>(this+DataTable+dt)
{
++++const+BindingFlags+flags+=+BindingFlags.Public+%7C+BindingFlags.Instance;
++++var+columnNames+=+dt.Columns.Cast<DataColumn>()
++++++++.Select(c+=>+c.ColumnName)
++++++++.ToList();
++++var+objectProperties+=+typeof(T).GetProperties(flags);
++++var+targetList+=+dt.AsEnumerable().Select(dataRow+=>
++++{
++++++++var+instanceOfT+=+Activator.CreateInstance<T>();

++++++++foreach+(var+properties+in+objectProperties.Where(properties+=>+columnNames.Contains(properties.Name)+&&+dataRow[properties.Name]+!=+DBNull.Value))
++++++++{
++++++++++++properties.SetValue(instanceOfT,+dataRow[properties.Name],+null);
++++++++}
++++++++return+instanceOfT;
++++}).ToList();

++++return+targetList;
}


var+output+=+yourDataInstance.ToListof<targetModelType>();|code-block|syntax|javascript|1500293|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can create a extension function as :

<pre><code>public static List&lt;T&gt; ToListof&lt;T&gt;(this DataTable dt)
{
 const BindingFlags flags = BindingFlags.Public | BindingFlags.Instance;
 var columnNames = dt.Columns.Cast&lt;DataColumn&gt;()
 .Select(c =&gt; c.ColumnName)
 .ToList();
 var objectProperties = typeof(T).GetProperties(flags);
 var targetList = dt.AsEnumerable().Select(dataRow =&gt;
 {
 var instanceOfT = Activator.CreateInstance&lt;T&gt;();

 foreach (var properties in objectProperties.Where(properties =&gt; columnNames.Contains(properties.Name) &amp;&amp; dataRow[properties.Name] != DBNull.Value))
 {
 properties.SetValue(instanceOfT, dataRow[properties.Name], null);
 }
 return instanceOfT;
 }).ToList();

 return targetList;
}


var output = yourDataInstance.ToListof&lt;targetModelType&gt;();
</code></pre>

blocks|key|1715147|text|如果您只想从"ID“int字段返回一个值列表，您可以使用...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1715148|List<int>+ids+=+(from+row+in+dt.AsEnumerable()+select+Convert.ToInt32(row["ID"])).ToList();|code-block|syntax|javascript|1715149|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you just want a list of values from the "ID" int field returned, you could use...

<pre><code>List&lt;int&gt; ids = (from row in dt.AsEnumerable() select Convert.ToInt32(row["ID"])).ToList();
</code></pre>

blocks|key|1715266|text|我对这个答案(https://stackoverflow.com/a/24588210/4489664)中的代码添加了一些修改，因为对于可以为空的类型，它将返回异常|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1715267|public+static+List<T>+DataTableToList<T>(this+DataTable+table)+where+T:+new()
{
++++List<T>+list+=+new+List<T>();
++++var+typeProperties+=+typeof(T).GetProperties().Select(propertyInfo+=>+new
++++++++{
++++++++++++PropertyInfo+=+propertyInfo,
++++++++++++Type+=+Nullable.GetUnderlyingType(propertyInfo.PropertyType)+??+propertyInfo.PropertyType
++++++++}).ToList();

++++foreach+(var+row+in+table.Rows.Cast<DataRow>())
++++{
++++++++T+obj+=+new+T();
++++++++foreach+(var+typeProperty+in+typeProperties)
++++++++{
++++++++++++object+value+=+row[typeProperty.PropertyInfo.Name];
++++++++++++object+safeValue+=+value+==+null+%7C%7C+DBNull.Value.Equals(value)
++++++++++++++++?+null
++++++++++++++++:+Convert.ChangeType(value,+typeProperty.Type);

++++++++++++typeProperty.PropertyInfo.SetValue(obj,+safeValue,+null);
++++++++}
++++++++list.Add(obj);
++++}
++++return+list;
}|code-block|syntax|javascript|1715268|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/24588210/4489664^0|7|18|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

I have added some modification to the code from this answer (<a href="https://stackoverflow.com/a/24588210/4489664">https://stackoverflow.com/a/24588210/4489664</a>) because for nullable Types it will return exception 

<pre><code>public static List&lt;T&gt; DataTableToList&lt;T&gt;(this DataTable table) where T: new()
{
 List&lt;T&gt; list = new List&lt;T&gt;();
 var typeProperties = typeof(T).GetProperties().Select(propertyInfo =&gt; new
 {
 PropertyInfo = propertyInfo,
 Type = Nullable.GetUnderlyingType(propertyInfo.PropertyType) ?? propertyInfo.PropertyType
 }).ToList();

 foreach (var row in table.Rows.Cast&lt;DataRow&gt;())
 {
 T obj = new T();
 foreach (var typeProperty in typeProperties)
 {
 object value = row[typeProperty.PropertyInfo.Name];
 object safeValue = value == null || DBNull.Value.Equals(value)
 ? null
 : Convert.ChangeType(value, typeProperty.Type);

 typeProperty.PropertyInfo.SetValue(obj, safeValue, null);
 }
 list.Add(obj);
 }
 return list;
}
</code></pre>

blocks|key|1715086|text|using+System.Data;


var+myEnumerable+=+myDataTable.AsEnumerable();

List<MyClass>+myClassList+=
++++(from+item+in+myEnumerable
+++++select+new+MyClass{
+++++++++MyClassProperty1+=+item.Field<string>("DataTableColumnName1"),
+++++++++MyClassProperty2+=+item.Field<string>("DataTableColumnName2")
++++}).ToList();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1715087|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>using System.Data;


var myEnumerable = myDataTable.AsEnumerable();

List&lt;MyClass&gt; myClassList =
 (from item in myEnumerable
 select new MyClass{
 MyClassProperty1 = item.Field&lt;string&gt;("DataTableColumnName1"),
 MyClassProperty2 = item.Field&lt;string&gt;("DataTableColumnName2")
 }).ToList();
</code></pre>

blocks|key|1499990|text|同样，使用3.5你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1499991|dt.Select().ToList()|code-block|syntax|javascript|1499992|BRGDS|1499993|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Again, using 3.5 you may do it like:

<pre><code>dt.Select().ToList()
</code></pre>

BRGDS

blocks|key|1715183|text|//+this+is+better+suited+for+expensive+object+creation/initialization
IEnumerable<Employee>+ParseEmployeeTable(DataTable+dtEmployees)
{
++++var+employees+=+new+ConcurrentBag<Employee>();

++++Parallel.ForEach(dtEmployees.AsEnumerable(),+(dr)+=>
++++{
++++++++employees.Add(new+Employee()+
++++++++{
++++++++++++_FirstName+=+dr["FirstName"].ToString(),
++++++++++++_LastName+=+dr["Last_Name"].ToString()
++++++++});
++++});

++++return+employees;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1715184|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>// this is better suited for expensive object creation/initialization
IEnumerable&lt;Employee&gt; ParseEmployeeTable(DataTable dtEmployees)
{
 var employees = new ConcurrentBag&lt;Employee&gt;();

 Parallel.ForEach(dtEmployees.AsEnumerable(), (dr) =&gt;
 {
 employees.Add(new Employee() 
 {
 _FirstName = dr["FirstName"].ToString(),
 _LastName = dr["Last_Name"].ToString()
 });
 });

 return employees;
}
</code></pre>

blocks|key|1499864|text|一种更“神奇”的方式，不需要.NET+3.5。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1499865|例如，如果DBDatatable返回单列的Guids+(在SQL中是唯一标识符)，那么您可以使用：|offset|length|style|CODE|1499866|Dim+gList+As+New+List(Of+Guid)
gList.AddRange(DirectCast(DBDataTable.Select(),+IEnumerable(Of+Guid)))|code-block|syntax|javascript|1499867|entityMap^0|0|5|B|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@$D|Q|E|R|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|S|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

A more 'magic' way, and doesn't need .NET 3.5.

If, for example, <code>DBDatatable</code> was returning a single column of Guids (uniqueidentifier in SQL) then you could use:

<pre><code>Dim gList As New List(Of Guid)
gList.AddRange(DirectCast(DBDataTable.Select(), IEnumerable(Of Guid)))
</code></pre>

blocks|key|1714983|text|DataTable.Select()不会按照它们在数据表中出现的顺序给出行。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1714984|如果顺序很重要，我觉得迭代datarow集合并形成一个列表是正确的方法，或者您也可以使用DataTable.Select(string+filterexpression,+string+sort)重载。|1714985|但是这个重载可能并不能处理所有的排序(比如order+by+case+...)SQL提供的。|1714986|entityMap^0|0|I|0|18|1I|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|R|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|K|$]]

<code>DataTable.Select()</code> doesnt give the Rows in the order they were present in the datatable.

If order is important I feel iterating over the datarow collection and forming a List is the right way to go or you could also use overload of <code>DataTable.Select(string filterexpression, string sort)</code>.

But this overload may not handle all the ordering (like order by case ...) that SQL provides.

blocks|key|1715171|text|DataTable+dt;+++//+datatable+should+contains+datacolumns+with+Id,Name

List<Employee>+employeeList=new+List<Employee>();++//+Employee+should+contain++EmployeeId,+EmployeeName+as+properties

foreach+(DataRow+dr+in+dt.Rows)
{
++++employeeList.Add(new+Employee{EmployeeId=dr.Id,EmplooyeeName=dr.Name});
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1715172|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>DataTable dt; // datatable should contains datacolumns with Id,Name

List&lt;Employee&gt; employeeList=new List&lt;Employee&gt;(); // Employee should contain EmployeeId, EmployeeName as properties

foreach (DataRow dr in dt.Rows)
{
 employeeList.Add(new Employee{EmployeeId=dr.Id,EmplooyeeName=dr.Name});
}
</code></pre>

blocks|key|1500258|text|使用System.Data命名空间，然后您将获得.AsEnumerable()。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1500259|entityMap^0|2|B|O|F|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

Use <code>System.Data</code> namespace then you will get <code>.AsEnumerable()</code>.

blocks|key|1715336|text|Output|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1715337|public+class+ModelUser
{
++++#region+Model

++++private+string+_username;
++++private+string+_userpassword;
++++private+string+_useremail;
++++private+int+_userid;

++++///+<summary>
++++///+
++++///+</summary>
++++public+int+userid
++++{
++++++++set+{+_userid+=+value;+}
++++++++get+{+return+_userid;+}
++++}


++++///+<summary>
++++///+
++++///+</summary>

++++public+string+username
++++{
++++++++set+{+_username+=+value;+}
++++++++get+{+return+_username;+}
++++}

++++///+<summary>
++++///+
++++///+</summary>
++++public+string+useremail
++++{
++++++++set+{+_useremail+=+value;+}
++++++++get+{+return+_useremail;+}
++++}

++++///+<summary>
++++///+
++++///+</summary>
++++public+string+userpassword
++++{
++++++++set+{+_userpassword+=+value;+}
++++++++get+{+return+_userpassword;+}
++++}
++++#endregion+Model
}

public+List<ModelUser>+DataTableToList(DataTable+dt)
{
++++List<ModelUser>+modelList+=+new+List<ModelUser>();
++++int+rowsCount+=+dt.Rows.Count;
++++if+(rowsCount+>+0)
++++{
++++++++ModelUser+model;
++++++++for+(int+n+=+0;+n+<+rowsCount;+n%2B%2B)
++++++++{
++++++++++++model+=+new+ModelUser();

++++++++++++model.userid+=+(int)dt.Rows[n]["userid"];
++++++++++++model.username+=+dt.Rows[n]["username"].ToString();
++++++++++++model.useremail+=+dt.Rows[n]["useremail"].ToString();
++++++++++++model.userpassword+=+dt.Rows[n]["userpassword"].ToString();

++++++++++++modelList.Add(model);
++++++++}
++++}
++++return+modelList;
}

static+DataTable+GetTable()
{
++++//+Here+we+create+a+DataTable+with+four+columns.
++++DataTable+table+=+new+DataTable();
++++table.Columns.Add("userid",+typeof(int));
++++table.Columns.Add("username",+typeof(string));
++++table.Columns.Add("useremail",+typeof(string));
++++table.Columns.Add("userpassword",+typeof(string));

++++//+Here+we+add+five+DataRows.
++++table.Rows.Add(25,+"Jame",+"Jame@hotmail.com",+DateTime.Now.ToString());
++++table.Rows.Add(50,+"luci",+"luci@hotmail.com",+DateTime.Now.ToString());
++++table.Rows.Add(10,+"Andrey",+"Andrey@hotmail.com",+DateTime.Now.ToString());
++++table.Rows.Add(21,+"Michael",+"Michael@hotmail.com",+DateTime.Now.ToString());
++++table.Rows.Add(100,+"Steven",+"Steven@hotmail.com",+DateTime.Now.ToString());
++++return+table;
}

protected+void+Page_Load(object+sender,+EventArgs+e)
{
++++List<ModelUser>+userList+=+new+List<ModelUser>();

++++DataTable+dt+=+GetTable();

++++userList+=+DataTableToList(dt);

++++gv.DataSource+=+userList;
++++gv.DataBind();
}[enter+image+description+here][1]|code-block|syntax|javascript|1715338|</asp:GridView>
</div>|1715339|entityMap|0|LINK|mutability|MUTABLE|url|http://i.stack.imgur.com/dGz6P.png^0|0|6|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|F|7|X|8|@]|9|@]|C|$G|H]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

<a href="http://i.stack.imgur.com/dGz6P.png" rel="nofollow">Output</a>

<pre><code>public class ModelUser
{
 #region Model

 private string _username;
 private string _userpassword;
 private string _useremail;
 private int _userid;

 /// &lt;summary&gt;
 /// 
 /// &lt;/summary&gt;
 public int userid
 {
 set { _userid = value; }
 get { return _userid; }
 }


 /// &lt;summary&gt;
 /// 
 /// &lt;/summary&gt;

 public string username
 {
 set { _username = value; }
 get { return _username; }
 }

 /// &lt;summary&gt;
 /// 
 /// &lt;/summary&gt;
 public string useremail
 {
 set { _useremail = value; }
 get { return _useremail; }
 }

 /// &lt;summary&gt;
 /// 
 /// &lt;/summary&gt;
 public string userpassword
 {
 set { _userpassword = value; }
 get { return _userpassword; }
 }
 #endregion Model
}

public List&lt;ModelUser&gt; DataTableToList(DataTable dt)
{
 List&lt;ModelUser&gt; modelList = new List&lt;ModelUser&gt;();
 int rowsCount = dt.Rows.Count;
 if (rowsCount &gt; 0)
 {
 ModelUser model;
 for (int n = 0; n &lt; rowsCount; n++)
 {
 model = new ModelUser();

 model.userid = (int)dt.Rows[n]["userid"];
 model.username = dt.Rows[n]["username"].ToString();
 model.useremail = dt.Rows[n]["useremail"].ToString();
 model.userpassword = dt.Rows[n]["userpassword"].ToString();

 modelList.Add(model);
 }
 }
 return modelList;
}

static DataTable GetTable()
{
 // Here we create a DataTable with four columns.
 DataTable table = new DataTable();
 table.Columns.Add("userid", typeof(int));
 table.Columns.Add("username", typeof(string));
 table.Columns.Add("useremail", typeof(string));
 table.Columns.Add("userpassword", typeof(string));

 // Here we add five DataRows.
 table.Rows.Add(25, "Jame", "Jame@hotmail.com", DateTime.Now.ToString());
 table.Rows.Add(50, "luci", "luci@hotmail.com", DateTime.Now.ToString());
 table.Rows.Add(10, "Andrey", "Andrey@hotmail.com", DateTime.Now.ToString());
 table.Rows.Add(21, "Michael", "Michael@hotmail.com", DateTime.Now.ToString());
 table.Rows.Add(100, "Steven", "Steven@hotmail.com", DateTime.Now.ToString());
 return table;
}

protected void Page_Load(object sender, EventArgs e)
{
 List&lt;ModelUser&gt; userList = new List&lt;ModelUser&gt;();

 DataTable dt = GetTable();

 userList = DataTableToList(dt);

 gv.DataSource = userList;
 gv.DataBind();
}[enter image description here][1]
</code></pre>


 

<pre><code>&lt;/asp:GridView&gt;
&lt;/div&gt;
</code></pre>

blocks|key|1500368|text|我们可以使用泛型方法将DataTable转换为List，而不是手动将DataTable转换为List。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1500369|注意：DataTable的ColumnName和Type的PropertyName应该相同。|1500370|调用下面的方法：|1500371|long+result+=+Utilities.ConvertTo<Student>(dt+,out+listStudent);

//+Generic+Method
public+class+Utilities
{
++++public+static+long+ConvertTo<T>(DataTable+table,+out+List<T>+entity)
++++{
++++++++long+returnCode+=+-1;
++++++++entity+=+null;

++++++++if+(table+==+null)
++++++++{
++++++++++++return+-1;
++++++++}

++++++++try
++++++++{
++++++++++++entity+=+ConvertTo<T>(table.Rows);
++++++++++++returnCode+=+0;
++++++++}

++++++++catch+(Exception+ex)
++++++++{
++++++++++++returnCode+=+1000;
++++++++}

++++++++return+returnCode;
++++}

++++static+List<T>+ConvertTo<T>(DataRowCollection+rows)
++++{
++++++++List<T>+list+=+null;
++++++++if+(rows+!=+null)
++++++++{
++++++++++++list+=+new+List<T>();

++++++++++++foreach+(DataRow+row+in+rows)
++++++++++++{
++++++++++++++++T+item+=+CreateItem<T>(row);
++++++++++++++++list.Add(item);
++++++++++++}
++++++++}

++++++++return+list;
++++}

++++static+T+CreateItem<T>(DataRow+row)
++++{
++++++++string+str+=+string.Empty;
++++++++string+strObj+=+string.Empty;

++++++++T+obj+=+default(T);

++++++++if+(row+!=+null)
++++++++{
++++++++++++obj+=+Activator.CreateInstance<T>();
++++++++++++strObj+=+obj.ToString();
++++++++++++NameValueCollection+objDictionary+=+new+NameValueCollection();

++++++++++++foreach+(DataColumn+column+in+row.Table.Columns)
++++++++++++{
++++++++++++++++PropertyInfo+prop+=+obj.GetType().GetProperty(column.ColumnName);

++++++++++++++++if+(prop+!=+null)
++++++++++++++++{
++++++++++++++++++++str+=+column.ColumnName;

++++++++++++++++++++try
++++++++++++++++++++{
++++++++++++++++++++++++objDictionary.Add(str,+row[str].ToString());
++++++++++++++++++++++++object+value+=+row[column.ColumnName];
++++++++++++++++++++++++Type+vType+=+obj.GetType();

++++++++++++++++++++++++if+(value+==+DBNull.Value)
++++++++++++++++++++++++{
++++++++++++++++++++++++++++if+(vType+==+typeof(int)+%7C%7C+vType+==+typeof(Int16)
+++++++++++++++++++++++++++++++++++++++++++++++++++++%7C%7C+vType+==+typeof(Int32)
+++++++++++++++++++++++++++++++++++++++++++++++++++++%7C%7C+vType+==+typeof(Int64)
+++++++++++++++++++++++++++++++++++++++++++++++++++++%7C%7C+vType+==+typeof(decimal)
+++++++++++++++++++++++++++++++++++++++++++++++++++++%7C%7C+vType+==+typeof(float)
+++++++++++++++++++++++++++++++++++++++++++++++++++++%7C%7C+vType+==+typeof(double))
++++++++++++++++++++++++++++{
++++++++++++++++++++++++++++++++value+=+0;
++++++++++++++++++++++++++++}

++++++++++++++++++++++++++++else+if+(vType+==+typeof(bool))
++++++++++++++++++++++++++++{
++++++++++++++++++++++++++++++++value+=+false;
++++++++++++++++++++++++++++}

++++++++++++++++++++++++++++else+if+(vType+==+typeof(DateTime))
++++++++++++++++++++++++++++{
++++++++++++++++++++++++++++++++value+=+DateTime.MaxValue;
++++++++++++++++++++++++++++}

++++++++++++++++++++++++++++else
++++++++++++++++++++++++++++{
++++++++++++++++++++++++++++++++value+=+null;
++++++++++++++++++++++++++++}

++++++++++++++++++++++++++++prop.SetValue(obj,+value,+null);
++++++++++++++++++++++++}

++++++++++++++++++++++++else
++++++++++++++++++++++++{
++++++++++++++++++++++++++++prop.SetValue(obj,+value,+null);
++++++++++++++++++++++++}
++++++++++++++++++++}

++++++++++++++++++++catch(Exception+ex)
++++++++++++++++++++{

++++++++++++++++++++}
++++++++++++++++}
++++++++++++}

++++++++++++PropertyInfo+ActionProp+=+obj.GetType().GetProperty("ActionTemplateValue");

++++++++++++if+(ActionProp+!=+null)
++++++++++++{
++++++++++++++++object+ActionValue+=+objDictionary;
++++++++++++++++ActionProp.SetValue(obj,+ActionValue,+null);
++++++++++++}
++++++++}

++++++++return+obj;
++++}
}|code-block|syntax|javascript|1500372|entityMap^0|B|9|N|4|Y|9|1A|4|0|3|9|D|A|O|4|T|C|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|18|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|19|8|@]|D|@]|E|$M|N]]|$1|O|3|-4|5|6|7|1A|8|@]|D|@]|E|$]]]|P|$]]

We can use a Generic Method for converting <code>DataTable</code> to <code>List</code> instead of manually converting a <code>DataTable</code> to <code>List</code>.

Note: <code>DataTable</code>'s <code>ColumnName</code> and <code>Type</code>'s <code>PropertyName</code> should be same.

Call the below Method:

<pre><code>long result = Utilities.ConvertTo&lt;Student&gt;(dt ,out listStudent);

// Generic Method
public class Utilities
{
 public static long ConvertTo&lt;T&gt;(DataTable table, out List&lt;T&gt; entity)
 {
 long returnCode = -1;
 entity = null;

 if (table == null)
 {
 return -1;
 }

 try
 {
 entity = ConvertTo&lt;T&gt;(table.Rows);
 returnCode = 0;
 }

 catch (Exception ex)
 {
 returnCode = 1000;
 }

 return returnCode;
 }

 static List&lt;T&gt; ConvertTo&lt;T&gt;(DataRowCollection rows)
 {
 List&lt;T&gt; list = null;
 if (rows != null)
 {
 list = new List&lt;T&gt;();

 foreach (DataRow row in rows)
 {
 T item = CreateItem&lt;T&gt;(row);
 list.Add(item);
 }
 }

 return list;
 }

 static T CreateItem&lt;T&gt;(DataRow row)
 {
 string str = string.Empty;
 string strObj = string.Empty;

 T obj = default(T);

 if (row != null)
 {
 obj = Activator.CreateInstance&lt;T&gt;();
 strObj = obj.ToString();
 NameValueCollection objDictionary = new NameValueCollection();

 foreach (DataColumn column in row.Table.Columns)
 {
 PropertyInfo prop = obj.GetType().GetProperty(column.ColumnName);

 if (prop != null)
 {
 str = column.ColumnName;

 try
 {
 objDictionary.Add(str, row[str].ToString());
 object value = row[column.ColumnName];
 Type vType = obj.GetType();

 if (value == DBNull.Value)
 {
 if (vType == typeof(int) || vType == typeof(Int16)
 || vType == typeof(Int32)
 || vType == typeof(Int64)
 || vType == typeof(decimal)
 || vType == typeof(float)
 || vType == typeof(double))
 {
 value = 0;
 }

 else if (vType == typeof(bool))
 {
 value = false;
 }

 else if (vType == typeof(DateTime))
 {
 value = DateTime.MaxValue;
 }

 else
 {
 value = null;
 }

 prop.SetValue(obj, value, null);
 }

 else
 {
 prop.SetValue(obj, value, null);
 }
 }

 catch(Exception ex)
 {

 }
 }
 }

 PropertyInfo ActionProp = obj.GetType().GetProperty("ActionTemplateValue");

 if (ActionProp != null)
 {
 object ActionValue = objDictionary;
 ActionProp.SetValue(obj, ActionValue, null);
 }
 }

 return obj;
 }
}
</code></pre>

blocks|key|1500424|text|您可以使用类似于datatable的泛型方法来泛型列表|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1500425|public+static+List<T>+DataTableToList<T>(this+DataTable+table)+where+T+:+class,+new()
{
++++try
++++{
++++++++List<T>+list+=+new+List<T>();

++++++++foreach+(var+row+in+table.AsEnumerable())
++++++++{
++++++++++++T+obj+=+new+T();

++++++++++++foreach+(var+prop+in+obj.GetType().GetProperties())
++++++++++++{
++++++++++++++++try
++++++++++++++++{
++++++++++++++++++++PropertyInfo+propertyInfo+=+obj.GetType().GetProperty(prop.Name);
++++++++++++++++++++if+(propertyInfo.PropertyType.IsEnum)
++++++++++++++++++++{
++++++++++++++++++++++++propertyInfo.SetValue(obj,+Enum.Parse(propertyInfo.PropertyType,+row[prop.Name].ToString()));
++++++++++++++++++++}
++++++++++++++++++++else
++++++++++++++++++++{
++++++++++++++++++++++++propertyInfo.SetValue(obj,+Convert.ChangeType(row[prop.Name],+propertyInfo.PropertyType),+null);
++++++++++++++++++++}++++++++++++++++++++++++++
++++++++++++++++}
++++++++++++++++catch
++++++++++++++++{
++++++++++++++++++++continue;
++++++++++++++++}
++++++++++++}

++++++++++++list.Add(obj);
++++++++}

++++++++return+list;
++++}
++++catch
++++{
++++++++return+null;
++++}
}|code-block|syntax|javascript|1500426|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can use a generic method like that for datatable to generic list 

<pre><code>public static List&lt;T&gt; DataTableToList&lt;T&gt;(this DataTable table) where T : class, new()
{
 try
 {
 List&lt;T&gt; list = new List&lt;T&gt;();

 foreach (var row in table.AsEnumerable())
 {
 T obj = new T();

 foreach (var prop in obj.GetType().GetProperties())
 {
 try
 {
 PropertyInfo propertyInfo = obj.GetType().GetProperty(prop.Name);
 if (propertyInfo.PropertyType.IsEnum)
 {
 propertyInfo.SetValue(obj, Enum.Parse(propertyInfo.PropertyType, row[prop.Name].ToString()));
 }
 else
 {
 propertyInfo.SetValue(obj, Convert.ChangeType(row[prop.Name], propertyInfo.PropertyType), null);
 } 
 }
 catch
 {
 continue;
 }
 }

 list.Add(obj);
 }

 return list;
 }
 catch
 {
 return null;
 }
}
</code></pre>

blocks|key|1500451|text|将DataTable转换为通用Dictionary|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1500452|public+static+Dictionary<object,IList<dynamic>>+DataTable2Dictionary(DataTable+dt)
{
++++Dictionary<object,+IList<dynamic>>+dict+=+new+Dictionary<dynamic,+IList<dynamic>>();

++++foreach(DataColumn+column+in+dt.Columns)
++++{
++++++++IList<dynamic>+ts+=+dt.AsEnumerable()
++++++++++++++++++++++++++++++.Select(r+=>+r.Field<dynamic>(column.ToString()))
++++++++++++++++++++++++++++++.ToList();
++++++++dict.Add(column,+ts);
++++}
++++return+dict;
}|code-block|syntax|javascript|1500453|entityMap^0|1|9|F|A|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

Converting <code>DataTable</code> to Generic <code>Dictionary</code> 

<pre><code>public static Dictionary&lt;object,IList&lt;dynamic&gt;&gt; DataTable2Dictionary(DataTable dt)
{
 Dictionary&lt;object, IList&lt;dynamic&gt;&gt; dict = new Dictionary&lt;dynamic, IList&lt;dynamic&gt;&gt;();

 foreach(DataColumn column in dt.Columns)
 {
 IList&lt;dynamic&gt; ts = dt.AsEnumerable()
 .Select(r =&gt; r.Field&lt;dynamic&gt;(column.ToString()))
 .ToList();
 dict.Add(column, ts);
 }
 return dict;
}
</code></pre>

blocks|key|1715540|text|使用扩展名：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1715541|public+static+class+Extensions
{
++++#region+Convert+Datatable+To+List
++++public+static+IList<T>+ToList<T>(this+DataTable+table)+where+T+:+new()
++++{
++++++++IList<PropertyInfo>+properties+=+typeof(T).GetProperties().ToList();
++++++++IList<T>+result+=+new+List<T>();

++++++++foreach+(var+row+in+table.Rows)
++++++++{
++++++++++++var+item+=+CreateItemFromRow<T>((DataRow)row,+properties);
++++++++++++result.Add(item);
++++++++}
++++++++return+result;
++++}
++++private+static+T+CreateItemFromRow<T>(DataRow+row,+IList<PropertyInfo>+properties)+where+T+:+new()
++++{
++++++++T+item+=+new+T();
++++++++foreach+(var+property+in+properties)
++++++++{
++++++++++++property.SetValue(item,+row[property.Name],+null);
++++++++}
++++++++return+item;
++++}
++++#endregion
}|code-block|syntax|javascript|1715542|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Use Extension :

<pre><code>public static class Extensions
{
 #region Convert Datatable To List
 public static IList&lt;T&gt; ToList&lt;T&gt;(this DataTable table) where T : new()
 {
 IList&lt;PropertyInfo&gt; properties = typeof(T).GetProperties().ToList();
 IList&lt;T&gt; result = new List&lt;T&gt;();

 foreach (var row in table.Rows)
 {
 var item = CreateItemFromRow&lt;T&gt;((DataRow)row, properties);
 result.Add(item);
 }
 return result;
 }
 private static T CreateItemFromRow&lt;T&gt;(DataRow row, IList&lt;PropertyInfo&gt; properties) where T : new()
 {
 T item = new T();
 foreach (var property in properties)
 {
 property.SetValue(item, row[property.Name], null);
 }
 return item;
 }
 #endregion
}
</code></pre>

blocks|key|1500546|text|您可以使用以下两个泛型函数|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1500547|private+static+List<T>+ConvertDataTable<T>(DataTable+dt)
++++{
++++++++List<T>+data+=+new+List<T>();
++++++++foreach+(DataRow+row+in+dt.Rows)
++++++++{
++++++++++++T+item+=+GetItem<T>(row);
++++++++++++data.Add(item);
++++++++}
++++++++return+data;
++++}
++++private+static+T+GetItem<T>(DataRow+dr)
++++{

++++++++Type+temp+=+typeof(T);
++++++++T+obj+=+Activator.CreateInstance<T>();

++++++++foreach+(DataColumn+column+in+dr.Table.Columns)
++++++++{
++++++++++++foreach+(PropertyInfo+pro+in+temp.GetProperties())
++++++++++++{
++++++++++++++++if+(pro.Name+==+column.ColumnName)
++++++++++++++++++++pro.SetValue(obj,+dr[column.ColumnName].ToString(),+null);
++++++++++++++++else
++++++++++++++++++++continue;
++++++++++++}
++++++++}
++++++++return+obj;
++++}|code-block|syntax|javascript|1500548|并使用它，如下所示|1500549|List<StudentScanExamsDTO>+studentDetails+=+ConvertDataTable<StudentScanExamsDTO>(dt);|1500550|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

you can use following two Generic functions

<pre><code>private static List&lt;T&gt; ConvertDataTable&lt;T&gt;(DataTable dt)
 {
 List&lt;T&gt; data = new List&lt;T&gt;();
 foreach (DataRow row in dt.Rows)
 {
 T item = GetItem&lt;T&gt;(row);
 data.Add(item);
 }
 return data;
 }
 private static T GetItem&lt;T&gt;(DataRow dr)
 {

 Type temp = typeof(T);
 T obj = Activator.CreateInstance&lt;T&gt;();

 foreach (DataColumn column in dr.Table.Columns)
 {
 foreach (PropertyInfo pro in temp.GetProperties())
 {
 if (pro.Name == column.ColumnName)
 pro.SetValue(obj, dr[column.ColumnName].ToString(), null);
 else
 continue;
 }
 }
 return obj;
 }
</code></pre>

and use it as following 

<pre><code>List&lt;StudentScanExamsDTO&gt; studentDetails = ConvertDataTable&lt;StudentScanExamsDTO&gt;(dt);
</code></pre>

blocks|key|1500578|text|lPerson+=+dt.AsEnumerable().Select(s+=>+new+Person()
++++++++{
++++++++++++Name+=+s.Field<string>("Name"),
++++++++++++SurName+=+s.Field<string>("SurName"),
++++++++++++Age+=+s.Field<int>("Age"),
++++++++++++InsertDate+=+s.Field<DateTime>("InsertDate")
++++++++}).ToList();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1500579|指向工作DotNetFiddle+Example的链接|unstyled|offset|length|1500580|++++using+System;
++++using+System.Collections.Generic;+++
++++using+System.Data;
++++using+System.Linq;
++++using+System.Data.DataSetExtensions;

++++public+static+void+Main()
++++{
++++++++DataTable+dt+=+new+DataTable();
++++++++dt.Columns.Add("Name",+typeof(string));
++++++++dt.Columns.Add("SurName",+typeof(string));
++++++++dt.Columns.Add("Age",+typeof(int));
++++++++dt.Columns.Add("InsertDate",+typeof(DateTime));

++++++++var+row1=+dt.NewRow();
++++++++row1["Name"]+=+"Adam";
++++++++row1["SurName"]+=+"Adam";
++++++++row1["Age"]+=+20;
++++++++row1["InsertDate"]+=+new+DateTime(2020,+1,+1);
++++++++dt.Rows.Add(row1);

++++++++var+row2+=+dt.NewRow();
++++++++row2["Name"]+=+"John";
++++++++row2["SurName"]+=+"Smith";
++++++++row2["Age"]+=+25;
++++++++row2["InsertDate"]+=+new+DateTime(2020,+3,+12);
++++++++dt.Rows.Add(row2);

++++++++var+row3+=+dt.NewRow();
++++++++row3["Name"]+=+"Jack";
++++++++row3["SurName"]+=+"Strong";
++++++++row3["Age"]+=+32;
++++++++row3["InsertDate"]+=+new+DateTime(2020,+5,+20);
++++++++dt.Rows.Add(row3);

++++++++List<Person>+lPerson+=+new+List<Person>();
++++++++lPerson+=+dt.AsEnumerable().Select(s+=>+new+Person()
++++++++{
++++++++++++Name+=+s.Field<string>("Name"),
++++++++++++SurName+=+s.Field<string>("SurName"),
++++++++++++Age+=+s.Field<int>("Age"),
++++++++++++InsertDate+=+s.Field<DateTime>("InsertDate")
++++++++}).ToList();
++++++++
++++++++foreach(Person+pers+in+lPerson)
++++++++{
++++++++++++Console.WriteLine("{0}+{1}+{2}+{3}",+pers.Name,+pers.SurName,+pers.Age,+pers.InsertDate);
++++++++}
++++}+++
++++
++++public+class+Person
++++{
++++++++public+string+Name+{+get;+set;+}
++++++++public+string+SurName+{+get;+set;+}
++++++++public+int+Age+{+get;+set;+}
++++++++public+DateTime+InsertDate+{+get;+set;+}
++++}
}|1500581|entityMap|0|LINK|mutability|MUTABLE|url|https://dotnetfiddle.net/jPozFN^0|0|4|K|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|T|8|@]|9|@$G|U|H|V|1|W]]|A|$]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$B|C]]|$1|K|3|-4|5|F|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

<pre><code>lPerson = dt.AsEnumerable().Select(s =&gt; new Person()
 {
 Name = s.Field&lt;string&gt;(&quot;Name&quot;),
 SurName = s.Field&lt;string&gt;(&quot;SurName&quot;),
 Age = s.Field&lt;int&gt;(&quot;Age&quot;),
 InsertDate = s.Field&lt;DateTime&gt;(&quot;InsertDate&quot;)
 }).ToList();
</code></pre>
Link to working <a href="https://dotnetfiddle.net/jPozFN" rel="nofollow noreferrer">DotNetFiddle Example</a>
<pre><code> using System;
 using System.Collections.Generic; 
 using System.Data;
 using System.Linq;
 using System.Data.DataSetExtensions;

 public static void Main()
 {
 DataTable dt = new DataTable();
 dt.Columns.Add(&quot;Name&quot;, typeof(string));
 dt.Columns.Add(&quot;SurName&quot;, typeof(string));
 dt.Columns.Add(&quot;Age&quot;, typeof(int));
 dt.Columns.Add(&quot;InsertDate&quot;, typeof(DateTime));

 var row1= dt.NewRow();
 row1[&quot;Name&quot;] = &quot;Adam&quot;;
 row1[&quot;SurName&quot;] = &quot;Adam&quot;;
 row1[&quot;Age&quot;] = 20;
 row1[&quot;InsertDate&quot;] = new DateTime(2020, 1, 1);
 dt.Rows.Add(row1);

 var row2 = dt.NewRow();
 row2[&quot;Name&quot;] = &quot;John&quot;;
 row2[&quot;SurName&quot;] = &quot;Smith&quot;;
 row2[&quot;Age&quot;] = 25;
 row2[&quot;InsertDate&quot;] = new DateTime(2020, 3, 12);
 dt.Rows.Add(row2);

 var row3 = dt.NewRow();
 row3[&quot;Name&quot;] = &quot;Jack&quot;;
 row3[&quot;SurName&quot;] = &quot;Strong&quot;;
 row3[&quot;Age&quot;] = 32;
 row3[&quot;InsertDate&quot;] = new DateTime(2020, 5, 20);
 dt.Rows.Add(row3);

 List&lt;Person&gt; lPerson = new List&lt;Person&gt;();
 lPerson = dt.AsEnumerable().Select(s =&gt; new Person()
 {
 Name = s.Field&lt;string&gt;(&quot;Name&quot;),
 SurName = s.Field&lt;string&gt;(&quot;SurName&quot;),
 Age = s.Field&lt;int&gt;(&quot;Age&quot;),
 InsertDate = s.Field&lt;DateTime&gt;(&quot;InsertDate&quot;)
 }).ToList();
 
 foreach(Person pers in lPerson)
 {
 Console.WriteLine(&quot;{0} {1} {2} {3}&quot;, pers.Name, pers.SurName, pers.Age, pers.InsertDate);
 }
 } 
 
 public class Person
 {
 public string Name { get; set; }
 public string SurName { get; set; }
 public int Age { get; set; }
 public DateTime InsertDate { get; set; }
 }
}
</code></pre>

blocks|key|1500629|text|如果有人想创建自定义函数来将datatable转换为list|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1500630|class+Program
{
++++static+void+Main(string[]+args)
++++{
++++++++DataTable+table+=+GetDataTable();
++++++++var+sw+=+new+Stopwatch();

++++++++sw.Start();
++++++++LinqMethod(table);
++++++++sw.Stop();
++++++++Console.WriteLine("Elapsed+time+for+Linq+Method={0}",+sw.ElapsedMilliseconds);

++++++++sw.Reset();

++++++++sw.Start();
++++++++ForEachMethod(table);
++++++++sw.Stop();
++++++++Console.WriteLine("Elapsed+time+for+Foreach+method={0}",+sw.ElapsedMilliseconds);

++++++++Console.ReadKey();
++++}

++++private+static+DataTable+GetDataTable()
++++{
++++++++var+table+=+new+DataTable();
++++++++table.Columns.Add("ID",+typeof(double));
++++++++table.Columns.Add("CategoryName",+typeof(string));
++++++++table.Columns.Add("Active",+typeof(double));

++++++++var+rand+=+new+Random();

++++++++for+(int+i+=+0;+i+<+100000;+i%2B%2B)
++++++++{
++++++++++++table.Rows.Add(i,+"name"+%2B+i,++rand.Next(0,+2));
++++++++}
++++++++return+table;
++++}

++++private+static+void+LinqMethod(DataTable+table)
++++{
++++++++var+list+=+table.AsEnumerable()
++++++++++++.Skip(1)
++++++++++++.Select(dr+=>
++++++++++++++++new+Category
++++++++++++++++{
++++++++++++++++++++Id+=+Convert.ToInt32(dr.Field<double>("ID")),
++++++++++++++++++++CategoryName+=+dr.Field<string>("CategoryName"),++++++++++++++++++++++
++++++++++++++++++++IsActive+=
++++++++++++++++++++++++++++dr.Field<double>("Active")+==+1+?+true+:+false
++++++++++++++++}).ToList();
++++}
++++private+static+void+ForEachMethod(DataTable+table)
++++{
++++++++var+categoryList+=+new+List<Category>(table.Rows.Count);
++++++++foreach+(DataRow+row+in+table.Rows)
++++++++{
++++++++++++var+values+=+row.ItemArray;
++++++++++++var+category+=+new+Category()
++++++++++++{
++++++++++++++++Id+=+Convert.ToInt32(values[0]),
++++++++++++++++CategoryName+=+Convert.ToString(values[1]),+++++++++++++++++++
++++++++++++++++IsActive+=+(double)values[2]+==+1+?+true+:+false
++++++++++++};
++++++++++++categoryList.Add(category);
++++++++}
++++}

++++private+class+Category
++++{
++++++++public+int+Id+{+get;+set;+}
++++++++public+string+CategoryName+{+get;+set;+}
++++++++public+bool+IsActive+{+get;+set;+}
++++}
}|code-block|syntax|javascript|1500631|如果我们执行上面的代码，Foreach方法在56ms内完成，而linq+one则需要101ms+(+1000条记录)。所以Foreach方法更好用。来源：Ways+to+Convert+Datatable+to+List+in+C#+(with+performance+test+example)|offset|length|1500632|entityMap|0|LINK|mutability|MUTABLE|url|https://qawithexperts.com/article/c-/ways-to-convert-datatable-to-list-in-c-with-performance-test/93^0|0|0|25|1Z|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

If anyone want's to create custom function to convert datatable to list
<pre><code>class Program
{
 static void Main(string[] args)
 {
 DataTable table = GetDataTable();
 var sw = new Stopwatch();

 sw.Start();
 LinqMethod(table);
 sw.Stop();
 Console.WriteLine(&quot;Elapsed time for Linq Method={0}&quot;, sw.ElapsedMilliseconds);

 sw.Reset();

 sw.Start();
 ForEachMethod(table);
 sw.Stop();
 Console.WriteLine(&quot;Elapsed time for Foreach method={0}&quot;, sw.ElapsedMilliseconds);

 Console.ReadKey();
 }

 private static DataTable GetDataTable()
 {
 var table = new DataTable();
 table.Columns.Add(&quot;ID&quot;, typeof(double));
 table.Columns.Add(&quot;CategoryName&quot;, typeof(string));
 table.Columns.Add(&quot;Active&quot;, typeof(double));

 var rand = new Random();

 for (int i = 0; i &lt; 100000; i++)
 {
 table.Rows.Add(i, &quot;name&quot; + i, rand.Next(0, 2));
 }
 return table;
 }

 private static void LinqMethod(DataTable table)
 {
 var list = table.AsEnumerable()
 .Skip(1)
 .Select(dr =&gt;
 new Category
 {
 Id = Convert.ToInt32(dr.Field&lt;double&gt;(&quot;ID&quot;)),
 CategoryName = dr.Field&lt;string&gt;(&quot;CategoryName&quot;), 
 IsActive =
 dr.Field&lt;double&gt;(&quot;Active&quot;) == 1 ? true : false
 }).ToList();
 }
 private static void ForEachMethod(DataTable table)
 {
 var categoryList = new List&lt;Category&gt;(table.Rows.Count);
 foreach (DataRow row in table.Rows)
 {
 var values = row.ItemArray;
 var category = new Category()
 {
 Id = Convert.ToInt32(values[0]),
 CategoryName = Convert.ToString(values[1]), 
 IsActive = (double)values[2] == 1 ? true : false
 };
 categoryList.Add(category);
 }
 }

 private class Category
 {
 public int Id { get; set; }
 public string CategoryName { get; set; }
 public bool IsActive { get; set; }
 }
}
</code></pre>
If we execute above code, Foreach method finishes in 56ms while linq one takes 101ms ( for 1000 records).
So Foreach method is better to use.
Source:<a href="https://qawithexperts.com/article/c-/ways-to-convert-datatable-to-list-in-c-with-performance-test/93" rel="nofollow noreferrer">Ways to Convert Datatable to List in C# (with performance test example)</a>

blocks|key|1500648|text|尝试使用Newtonsoft+Json：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1500649|var+json+=+JsonConvert.SerializeObject(dataTable);
var+YourConvertedDataType+=+JsonConvert.DeserializeObject<YourDataType>(json);|code-block|syntax|javascript|1500650|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

try this using Newtonsoft Json:
<pre><code>var json = JsonConvert.SerializeObject(dataTable);
var YourConvertedDataType = JsonConvert.DeserializeObject&lt;YourDataType&gt;(json);
</code></pre>

Currently, I'm using:

<pre><code>DataTable dt = CreateDataTableInSomeWay();

List&lt;DataRow&gt; list = new List&lt;DataRow&gt;(); 
foreach (DataRow dr in dt.Rows)
{
 list.Add(dr);
}
</code></pre>

Is there a better/magic way?

How do you convert a DataTable into a generic list?

目前，我使用的是：DataTable dt = CreateDataTableInSomeWay();List<DataRow> list = new List<DataRow>(); foreach (DataRow dr in dt.Rows){ list.Add(dr);}有没有更好的/神奇的方法？

问如何将DataTable转换为泛型列表？
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问如何将DataTable转换为泛型列表？
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