Linq 泛型查询

赋值给System.Func<T,TResult> fun类型

1，using System;

delegate string ConvertMethod(string inString);

public class DelegateExample
{
   public static void Main()
   {
      // Instantiate delegate to reference UppercaseString method
      ConvertMethod convertMeth = UppercaseString;
      string name = "Dakota";
      // Use delegate instance to call UppercaseString method
      Console.WriteLine(convertMeth(name));
   }

   private static string UppercaseString(string inputString)
   {
      return inputString.ToUpper();
   }
}

2，

using System;

public class GenericFunc
{
   public static void Main() { // Instantiate delegate to reference UppercaseString method
      Func<string, string> convertMethod = UppercaseString;
      string name = "Dakota";
      // Use delegate instance to call UppercaseString method
      Console.WriteLine(convertMethod(name));
   }

   private static string UppercaseString(string inputString)
   {
      return inputString.ToUpper();
   }
}

3，

using System;

public class Anonymous
{
   public static void Main()
   {
      Func<string, string> convert = delegate(string s)  //匿名方法，直接在方法中返回值。
         { return s.ToUpper();};

      string name = "Dakota";
      Console.WriteLine(convert(name));  
   }
}

 public static void Main()
   {
      Func<string, string> convert = s => s.ToUpper();  //赋值给拉吗达表达式
      string name = "Dakota";
      Console.WriteLine(convert(name));  
   }