blocks|key|1820281|text|对于只读控件，它们是相同的。对于双向数据绑定，您需要使用一个数据源，在该数据源中，您需要使用声明式数据绑定进行更新、插入等操作，您需要使用Bind。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1820282|例如，假设一个具有ItemTemplate和EditItemTemplate的GridView。如果在ItemTemplate中使用Bind或Eval，则没有区别。如果在EditItemTemplate中使用Eval，则无法将该值传递给网格绑定到的DataSource的Update方法。|1820283|1820284|更新:我想出了这个例子：|1820285|<%25@+Page+Language="C#"+%25>
<!DOCTYPE+html+PUBLIC+"-//W3C//DTD+XHTML+1.0+Transitional//EN"+"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html+xmlns="http://www.w3.org/1999/xhtml">
<head+runat="server">
++++<title>Data+binding+demo</title>
</head>
<body>
++++<form+id="form1"+runat="server">
++++++++<asp:GridView+
++++++++++++ID="grdTest"+
++++++++++++runat="server"+
++++++++++++AutoGenerateEditButton="true"+
++++++++++++AutoGenerateColumns="false"+
++++++++++++DataSourceID="mySource">
++++++++++++<Columns>
++++++++++++++++<asp:TemplateField>
++++++++++++++++++++<ItemTemplate>
++++++++++++++++++++++++<%25#+Eval("Name")+%25>
++++++++++++++++++++</ItemTemplate>
++++++++++++++++++++<EditItemTemplate>
++++++++++++++++++++++++<asp:TextBox+
++++++++++++++++++++++++++++ID="edtName"+
++++++++++++++++++++++++++++runat="server"+
++++++++++++++++++++++++++++Text='<%25#+Bind("Name")+%25>'+
++++++++++++++++++++++++/>
++++++++++++++++++++</EditItemTemplate>
++++++++++++++++</asp:TemplateField>
++++++++++++</Columns>
++++++++</asp:GridView>
++++</form>

++++<asp:ObjectDataSource+
++++++++ID="mySource"+
++++++++runat="server"
++++++++SelectMethod="Select"+
++++++++UpdateMethod="Update"+
++++++++TypeName="MyCompany.CustomDataSource"+/>
</body>
</html>|code-block|syntax|javascript|1820286|下面是作为对象数据源的自定义类的定义：|1820287|public+class+CustomDataSource
{
++++public+class+Model
++++{
++++++++public+string+Name+{+get;+set;+}
++++}

++++public+IEnumerable<Model>+Select()
++++{
++++++++return+new[]+
++++++++{
++++++++++++new+Model+{+Name+=+"some+value"+}
++++++++};
++++}

++++public+void+Update(string+Name)
++++{
++++++++//+This+method+will+be+called+if+you+used+Bind+for+the+TextBox
++++++++//+and+you+will+be+able+to+get+the+new+name+and+update+the
++++++++//+data+source+accordingly
++++}

++++public+void+Update()
++++{
++++++++//+This+method+will+be+called+if+you+used+Eval+for+the+TextBox
++++++++//+and+you+will+not+be+able+to+get+the+new+name+that+the+user
++++++++//+entered
++++}
}|1820288|entityMap^0|1X|4|0|9|C|M|G|1F|C|1U|4|1Z|4|2D|G|2W|4|3G|A|3R|6|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|F|3|G|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]|$9|17|A|18|B|C]|$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]|$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|1H|8|@]|D|@]|E|$]]|$1|I|3|J|5|6|7|1I|8|@]|D|@]|E|$]]|$1|K|3|L|5|M|7|1J|8|@]|D|@]|E|$N|O]]|$1|P|3|Q|5|6|7|1K|8|@]|D|@]|E|$]]|$1|R|3|S|5|M|7|1L|8|@]|D|@]|E|$N|O]]|$1|T|3|-4|5|6|7|1M|8|@]|D|@]|E|$]]]|U|$]]

For read-only controls they are the same. For 2 way databinding, using a datasource in which you want to update, insert, etc with declarative databinding, you'll need to use <code>Bind</code>.

Imagine for example a GridView with a <code>ItemTemplate</code> and <code>EditItemTemplate</code>. If you use <code>Bind</code> or <code>Eval</code> in the <code>ItemTemplate</code>, there will be no difference. If you use <code>Eval</code> in the <code>EditItemTemplate</code>, the value will not be able to be passed to the <code>Update</code> method of the <code>DataSource</code> that the grid is bound to.

<hr>

UPDATE: I've come up with this example:

<pre><code>&lt;%@ Page Language="C#" %&gt;
&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;

&lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
&lt;head runat="server"&gt;
 &lt;title&gt;Data binding demo&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
 &lt;form id="form1" runat="server"&gt;
 &lt;asp:GridView 
 ID="grdTest" 
 runat="server" 
 AutoGenerateEditButton="true" 
 AutoGenerateColumns="false" 
 DataSourceID="mySource"&gt;
 &lt;Columns&gt;
 &lt;asp:TemplateField&gt;
 &lt;ItemTemplate&gt;
 &lt;%# Eval("Name") %&gt;
 &lt;/ItemTemplate&gt;
 &lt;EditItemTemplate&gt;
 &lt;asp:TextBox 
 ID="edtName" 
 runat="server" 
 Text='&lt;%# Bind("Name") %&gt;' 
 /&gt;
 &lt;/EditItemTemplate&gt;
 &lt;/asp:TemplateField&gt;
 &lt;/Columns&gt;
 &lt;/asp:GridView&gt;
 &lt;/form&gt;

 &lt;asp:ObjectDataSource 
 ID="mySource" 
 runat="server"
 SelectMethod="Select" 
 UpdateMethod="Update" 
 TypeName="MyCompany.CustomDataSource" /&gt;
&lt;/body&gt;
&lt;/html&gt;
</code></pre>

And here's the definition of a custom class that serves as object data source:

<pre><code>public class CustomDataSource
{
 public class Model
 {
 public string Name { get; set; }
 }

 public IEnumerable&lt;Model&gt; Select()
 {
 return new[] 
 {
 new Model { Name = "some value" }
 };
 }

 public void Update(string Name)
 {
 // This method will be called if you used Bind for the TextBox
 // and you will be able to get the new name and update the
 // data source accordingly
 }

 public void Update()
 {
 // This method will be called if you used Eval for the TextBox
 // and you will not be able to get the new name that the user
 // entered
 }
}
</code></pre>

Can anyone show me some absolutely minimal ASP.NET code to understand <code>Eval()</code> and <code>Bind()</code>?

It is best if you provide me with two separate code-snippets or may be web-links.

Understanding ASP.NET Eval() and Bind()

谁能向我展示一些理解Eval()和Bind()的绝对最小的ASP.NET代码这是最好的，如果你提供给我两个单独的代码片段，或可能是网络链接。

问了解绑定Eval()和ASP.NET ()
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