Problem with Anonymous delegate in loop

TestForeachEventHandler.zip

   1: foreach (Test test in tests)

   2:             {

   3:                 Button button = new Button();

   4:                 button.Text = test.name;

   5:                 button.Click+=new EventHandler((object obj, EventArgs arg)=>{

   6:                     this.CreateTest(test);

   7:                 });

   8:                 this.flowLayoutPanel1.Controls.Add(button);

   9:             }

tests里有2个元素，分别为test1与test2, 程序会为每个test新建一个button, 设为button1,button2.
在button1的Click事件触发的时候，调用CreateTestFlow方法时，传递的参数会是test2而不是test1.

原因：

WTF: "Problems" with Anonymous Delegates, LINQ, Lambdas within "foreach" or "for" Loops这篇文章里的解释为：匿名委托里的test是对循环变量引用，在循环结束时该变量为最后个值，即’test2’.
如对foreach的理解相对困难的话，可以把foreach改为for,代码如下：

   1: for (int i=0;i 
    
   2: {
 
    
   3:     Button button = new Button();
 
    
   4:     button.Text = tests[i].name;
 
    
   5:     button.Click+=new EventHandler((object obj, EventArgs arg)=>{
 
    
   6:         this.CreateTest(tests[i]);
 
    
   7:     });
 
    
   8:     this.flowLayoutPanel1.Controls.Add(button);
 
    
   9: }
 
   

则此代码在运行时，会在第6行出现：ArgumentOutOfRangeException, Index was out of range.

解决方法：

在循环体里新建一变量，用来保存循环过程中的值。代码如下：

   1:  foreach (Test tes in tests)

   2:             {

   3:                 Test test = tes;

   4:                 Button button = new Button();

   5:                 button.Text = test.name;

   6:                 button.Click+=new EventHandler((object obj, EventArgs arg)=>{

   7:                     this.CreateTest(test);

   8:                 });

   9:                 this.flowLayoutPanel1.Controls.Add(button);

  10:             }