C # parameter keyword ref

The ref keyword allows the method to be passed by reference. The effect is that when the control is passed to the call method, any modifications made to the parameters in the method will be reflected in the change volume.

Example:

Int I =
10;
// View the value before calling the Method
Console. writeline ("before the method calling: I = {0}", I );

Useref (Ref I );

// View the value after the method is called
Console. writeline ("after the method calling: I = {0}", I );
Console. Readline ();

Public static
Void useref (ref
Int I)
{
I + = 100;
Console. writeline ("I = {0}", I );
}

 

The result is as follows:

From the above code, we can see that:

1. To use ref
Parameter, the method definition and call method must be explicitly usedRefKeywords

2. Pass to ref
The parameter must be initialized first.