了解c#2.0中的Anonymous Methods(匿名方法)

末蓝、 2021-11-17 12:18 193阅读 0赞

Anonymous Methods 是 C\#2.0的新特性之一，它允许我们在代码中创建一个内置的没有方法名的方法，将代码与委托实例相关联，从而使委托的实例化工作更加直观和方便，提高了代码的可读性和可维护性。下面来看一个简单的匿名方法的使用：

![ExpandedBlockStart.gif][] ![ContractedBlock.gif][ExpandedBlockStart.gif] private   int \[\] \_integers  =        ![dot.gif][ExpandedBlockStart.gif] \{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 \} ;  
![None.gif][ExpandedBlockStart.gif]  
![None.gif][ExpandedBlockStart.gif] int \[\] evenIntegers  =  Array.FindAll(\_integers,                            delegate ( int  integer)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][ExpandedBlockStart.gif]                            ![dot.gif][ExpandedBlockStart.gif] \{  
![InBlock.gif][ExpandedBlockStart.gif]                               return (integer%2 == 0);  
![ExpandedBlockEnd.gif][ExpandedBlockStart.gif]                           \}   
![None.gif][ExpandedBlockStart.gif]    );  
![None.gif][ExpandedBlockStart.gif]

上面的代码使用了匿名方法来获得数组中能被2整除的数，其中的匿名方法是：

![None.gif][ExpandedBlockStart.gif] delegate ( int  integer)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][ExpandedBlockStart.gif]     ![dot.gif][ExpandedBlockStart.gif] \{  
![InBlock.gif][ExpandedBlockStart.gif]        return (integer%2 == 0);  
![ExpandedBlockEnd.gif][ExpandedBlockStart.gif]    \}   
![None.gif][ExpandedBlockStart.gif]

如果我们不用匿名方法,我们就需要专门创建一个方法,如下:

![ExpandedBlockStart.gif][] ![ContractedBlock.gif][ExpandedBlockStart.gif] private   int \[\] \_integers  =   ![dot.gif][ExpandedBlockStart.gif] \{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 \} ;  
![None.gif][ExpandedBlockStart.gif]  
![None.gif][ExpandedBlockStart.gif] int \[\] evenIntegers  =  Array.FindAll(\_integers, IsEven);  
![None.gif][ExpandedBlockStart.gif]  
![None.gif][ExpandedBlockStart.gif] private   bool  IsEven( int  integer)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][ExpandedBlockStart.gif] ![dot.gif][ExpandedBlockStart.gif] \{  
![InBlock.gif][ExpandedBlockStart.gif]    return (integer%2 == 0);  
![ExpandedBlockEnd.gif][ExpandedBlockStart.gif]\}   
![None.gif][ExpandedBlockStart.gif]

匿名方法用于那种方法比较简单,而且不会在其他地方被调用的情况,我们还可以像下面这样用匿名方法:

![None.gif][ExpandedBlockStart.gif] button1.Click  \+=   
![None.gif][ExpandedBlockStart.gif]  
![None.gif][ExpandedBlockStart.gif]     delegate   
![ExpandedBlockStart.gif][]![ContractedBlock.gif][ExpandedBlockStart.gif]         ![dot.gif][ExpandedBlockStart.gif] \{  
![InBlock.gif][ExpandedBlockStart.gif]            MessageBox.Show("Hello");  
![ExpandedBlockEnd.gif][ExpandedBlockStart.gif]        \} ;  
![None.gif][ExpandedBlockStart.gif]

转载于:https://www.cnblogs.com/pw/archive/2006/06/24/434600.html

[ExpandedBlockStart.gif]: