ref and out parameters

 ref parameters

• The ref modifier causes arguments to be passed by reference

• The ref modifier has to be used in the method definition and the code that

   calls it

void RefFunction(ref int iP)

{

iP++;

}

Call statement:

int iNum = 10;

RefFunction(ref iNum);

// iNum is now 11

out parameters

• the out parameter is used in cases where you need to return a value from    a method, but not pass a value to the method.

• use out parameter to return more than one value from the method.

• out parameter will not have any initial values but must be assigned a value before the method terminates.

passing variable number of arguments

• Methods can have a variable number of arguments, called a parameter array

• params keyword declares parameter array

• This must be last argument of the method and there can be only one such

argument.

int Sum(params int[] aiArr) {

int iSum = 0;

foreach (int iNum in aiArr)

iSum += iNum;

return iSum;

}

int iTotal = Sum(13,87,34);