Methods in C# - Anonymous Methods

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Anonymous methods are a C# 2.0 feature that has been subsumed by C# 3.0 lambda expressions. An anonymous method is like a lambda expression, but it lacks the following features:

• Implicitly typed parameters
  
• Expression syntax (an anonymous method must always be a statement block)
  
• The ability to compile to an expression tree, by assigning toExpression<T>

To write an anonymous method, you include thedelegatekeyword followed by a parameter declaration and then a method body. For example:

  delegate int Transformer (int i);

  class Test
  {
    static void Main()
    {
      Transformer square = delegate (int x) {return x * x;};
     Console.WriteLine (square(3));   // 9
    }
  }

The following line:

  Transformer square = delegate (int x) {return x * x;};

is semantically equivalent to the following lambda expression:

  Transformer square =       (int x) => {return x * x;};

Or simply:

  Transformer square =             x => x * x;

Anonymous methods capture outer variables in the same way lambda expressions do.

Next: try Statements and Exceptions >>
 

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