blocks|key|1627811|text|是。您可以使用反射。如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1627812|Type+thisType+=+this.GetType();
MethodInfo+theMethod+=+thisType.GetMethod(TheCommandString);
theMethod.Invoke(this,+userParameters);|code-block|syntax|javascript|1627813|使用上面的代码，被调用的方法必须有访问修饰符public。如果调用非公共方法，则需要使用BindingFlags参数，例如BindingFlags.NonPublic+%7C+BindingFlags.Instance|offset|length|style|CODE|1627814|Type+thisType+=+this.GetType();
MethodInfo+theMethod+=+thisType
++++.GetMethod(TheCommandString,+BindingFlags.NonPublic+%7C+BindingFlags.Instance);
theMethod.Invoke(this,+userParameters);|1627815|entityMap^0|0|0|M|6|18|C|1P|1A|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]|$I|X|J|Y|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|P|$]]

Yes. You can use reflection. Something like this:
<pre class="lang-cs prettyprint-override"><code>Type thisType = this.GetType();
MethodInfo theMethod = thisType.GetMethod(TheCommandString);
theMethod.Invoke(this, userParameters);
</code></pre>
With the above code, the method which is invoked must have access modifier <code>public</code>. If calling a non-public method, one needs to use the <code>BindingFlags</code> parameter, e.g. <code>BindingFlags.NonPublic | BindingFlags.Instance</code>:
<pre class="lang-cs prettyprint-override"><code>Type thisType = this.GetType();
MethodInfo theMethod = thisType
 .GetMethod(TheCommandString, BindingFlags.NonPublic | BindingFlags.Instance);
theMethod.Invoke(this, userParameters);
</code></pre>

blocks|key|1413206|text|class+Program
++++{
++++++++static+void+Main(string[]+args)
++++++++{
++++++++++++Type+type+=+typeof(MyReflectionClass);
++++++++++++MethodInfo+method+=+type.GetMethod("MyMethod");
++++++++++++MyReflectionClass+c+=+new+MyReflectionClass();
++++++++++++string+result+=+(string)method.Invoke(c,+null);
++++++++++++Console.WriteLine(result);

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

++++public+class+MyReflectionClass
++++{
++++++++public+string+MyMethod()
++++++++{
++++++++++++return+DateTime.Now.ToString();
++++++++}
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1413207|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>class Program
 {
 static void Main(string[] args)
 {
 Type type = typeof(MyReflectionClass);
 MethodInfo method = type.GetMethod("MyMethod");
 MyReflectionClass c = new MyReflectionClass();
 string result = (string)method.Invoke(c, null);
 Console.WriteLine(result);

 }
 }

 public class MyReflectionClass
 {
 public string MyMethod()
 {
 return DateTime.Now.ToString();
 }
 }
</code></pre>

blocks|key|1627892|text|您可以使用反射调用类实例的方法，执行动态方法调用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1627893|假设您在实际实例(This)中有一个名为hello的方法：|1627894|string+methodName+=+"hello";

//Get+the+method+information+using+the+method+info+class
+MethodInfo+mi+=+this.GetType().GetMethod(methodName);

//Invoke+the+method
//+(null-+no+parameter+for+the+method+call
//+or+you+can+pass+the+array+of+parameters...)
mi.Invoke(this,+null);|code-block|syntax|javascript|1627895|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can invoke methods of a class instance using reflection, doing a dynamic method invocation:

Suppose that you have a method called hello in a the actual instance (this):

<pre><code>string methodName = "hello";

//Get the method information using the method info class
 MethodInfo mi = this.GetType().GetMethod(methodName);

//Invoke the method
// (null- no parameter for the method call
// or you can pass the array of parameters...)
mi.Invoke(this, null);
</code></pre>

blocks|key|1413293|text|一条细微的切线--如果您想要解析和计算包含(嵌套！)的整个表达式字符串函数，考虑NCalc+(http://ncalc.codeplex.com/和nuget)|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1413294|例如。对项目文档稍作修改：|1413295|//+the+expression+to+evaluate,+e.g.+from+user+input+(like+a+calculator+program,+hint+hint+college+students)
var+exprStr+=+"10+%2B+MyFunction(3,+6)";
Expression+e+=+new+Expression(exprString);

//+tell+it+how+to+handle+your+custom+function
e.EvaluateFunction+%2B=+delegate(string+name,+FunctionArgs+args)+{
++++++++if+(name+==+"MyFunction")
++++++++++++args.Result+=+(int)args.Parameters[0].Evaluate()+%2B+(int)args.Parameters[1].Evaluate();
++++};

//+confirm+it+worked
Debug.Assert(19+==+e.Evaluate());|code-block|syntax|javascript|1413296|在EvaluateFunction委托中，您将调用现有的函数。|style|CODE|1413297|entityMap|0|LINK|mutability|MUTABLE|url|http://ncalc.codeplex.com/^0|1B|Q|0|0|0|0|1|G|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|6|7|10|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|11|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|12|8|@$A|13|B|14|M|N]]|9|@]|C|$]]|$1|O|3|-4|5|6|7|15|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

A slight tangent -- if you want to parse and evaluate an entire expression string which contains (nested!) functions, consider NCalc (<a href="http://ncalc.codeplex.com/" rel="nofollow">http://ncalc.codeplex.com/</a> and nuget)

Ex. slightly modified from the project documentation:

<pre><code>// the expression to evaluate, e.g. from user input (like a calculator program, hint hint college students)
var exprStr = "10 + MyFunction(3, 6)";
Expression e = new Expression(exprString);

// tell it how to handle your custom function
e.EvaluateFunction += delegate(string name, FunctionArgs args) {
 if (name == "MyFunction")
 args.Result = (int)args.Parameters[0].Evaluate() + (int)args.Parameters[1].Evaluate();
 };

// confirm it worked
Debug.Assert(19 == e.Evaluate());
</code></pre>

And within the <code>EvaluateFunction</code> delegate you would call your existing function.

blocks|key|1628021|text|此代码可在我的控制台.Net应用程序中运行|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1628022|class+Program
{
++++static+void+Main(string[]+args)
++++{
++++++++string+method+=+args[0];+//+get+name+method
++++++++CallMethod(method);
++++}
++++
++++public+static+void+CallMethod(string+method)
++++{
++++++++try
++++++++{
++++++++++++Type+type+=+typeof(Program);
++++++++++++MethodInfo+methodInfo+=+type.GetMethod(method);
++++++++++++methodInfo.Invoke(method,+null);
++++++++}
++++++++catch(Exception+ex)
++++++++{
++++++++++++Console.WriteLine("Error:+"+%2B+ex.Message);
++++++++++++Console.ReadKey();
++++++++}
++++}
++++
++++public+static+void+Hello()
++++{
++++++++string+a+=+"hello+world!";
++++++++Console.WriteLine(a);
++++++++Console.ReadKey();
++++}
}|code-block|syntax|javascript|1628023|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|$]]

This code works in my console .Net application
<pre><code>class Program
{
 static void Main(string[] args)
 {
 string method = args[0]; // get name method
 CallMethod(method);
 }
 
 public static void CallMethod(string method)
 {
 try
 {
 Type type = typeof(Program);
 MethodInfo methodInfo = type.GetMethod(method);
 methodInfo.Invoke(method, null);
 }
 catch(Exception ex)
 {
 Console.WriteLine(&quot;Error: &quot; + ex.Message);
 Console.ReadKey();
 }
 }
 
 public static void Hello()
 {
 string a = &quot;hello world!&quot;;
 Console.WriteLine(a);
 Console.ReadKey();
 }
}
</code></pre>

blocks|key|1413344|text|使用类型动态，在C#+4.0中引入了动态。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1413345|++++dynamic+someClass+=+new+YourClass();
++++someClass.SomeMethod();

++++public+class+YourClass
++++{
++++++++public+void+SomeMethod()
++++++++{
++++++++++++Console.WriteLine("SomeMethod+called+using+dynamic+type");
++++++++}++++++++
++++}|code-block|syntax|javascript|1413346|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|$]]

Using Type dynamic, dynamic was introduced in C# 4.0.
<pre><code> dynamic someClass = new YourClass();
 someClass.SomeMethod();

 public class YourClass
 {
 public void SomeMethod()
 {
 Console.WriteLine(&quot;SomeMethod called using dynamic type&quot;);
 } 
 }
</code></pre>

I know in php you are able to make a call like:

<pre><code>$function_name = 'hello';
$function_name();

function hello() { echo 'hello'; }
</code></pre>

Is this possible in .Net?

Calling a function from a string in C#

我知道在php中你可以这样调用：$function_name = 'hello';$function_name();function hello() { echo 'hello'; }这在.Net中是可能的吗？

问在C#中从字符串调用函数
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