Parameter passing in C#Edit

There are four different ways of passing parameters to a method in C# which are as:

  1. Value
    • In this method a duplicate copy is made and sent to the called function, so if you change the value in the called method it won’t be changed in the calling method.
  2. Ref (reference)
    • Uses the addresses of the actual params. It requires ref keyword in front of variables. We use this process when we want to use or change the values of the params passed. The process of ref is bidirectional, we have to supply value and we get back processed value.
    public int sum(ref int a, ref int b)
...
int a = 10, b = 20;
obj.sum(ref a, ref b);
  3. Out (reference)
    • It does not create a new storage location and are passed by reference. It requires out keyword in front of variables. The process of out is unidirectional, we don’t have to supply value, but we get back the processed value.
    public int sum(int a, int b, out int c, out int d)
...
int a = 10, b = 20;
int c, d;
obj.sum(a, b, out c, out d);
  4. Params (parameter arrays)
    • params is used when we don’t know the number of parameters that will be passed to the called method. params should be a single dimensional or a jagged array.
    public void print(params int[] numbers)
int[] numbers = { 1, 2, 3, 4, 5, 6 };
int a = 10, b = 20, c = 30, d = 40;
obj.print(a, b, c, d);
obj.print(numbers);

See also