29.9 Using the - member access operator

29.9 Using the -> member access operator

Examine the program below.

 1: using System;  2:  3: public class TestClass{  4:  5:   public struct Temp{  6:     public int a;  7:     public int b;  8:     public void SaySomething(){  9:       Console.WriteLine("hi!"); 10:     } 11:   } 12: 13:   public unsafe static void Main(){ 14:     Temp temp = new Temp(); 15:     Temp* pTemp = &temp; 16: 17:     // invoke method of temp by indirection 18:  (*pTemp).SaySomething();  19: 20:     // access field of temp by indirection 21:  Console.WriteLine((*pTemp).a);  22:   } 23: } 

Output:

 c:\expt> hi! 0 

Line 18 invokes a method and line 21 retrieves the value of a field indirectly by applying the indirection operator on the pTemp pointer. C# has a simpler syntax to access a member. Instead of:

 (*pTemp).SaySomething(); 

it uses the -> operator like this:

 pTemp->SaySomething(); 

Similarly, the following two expressions are equivalent:

 (*pTemp).a pTemp->a 

The operand on the left of the -> operator must be a pointer type (except void* ), and the operand on the right must refer to an accessible member that matches the pointer's referent type.

The -> operator does not add new functionality to unsafe coding, it simply serves to simplify the syntax of potentially intimidating codes. This operator can only be used in an unsafe context.