Is there a way to omit out parameter? [duplicate]

Answer 1

You cannot do this, but there's no rule saying that you have to use the value that comes back. You can simply pass a temporary variable that you never use again.

C# 4.0 allows optional parameters, but out parameters can't be optional.

EDIT: BTW, you can also overload the method:

int DoStuff()
{
    int temp;
    return DoStuff(out temp);
}

int DoStuff(out outParam)
{
    //...
}

Answer 2

Not sure about C#, but in VB.Net you can simply pass in a constant to an output (byref) parameter. So if you have an integer, as an output parameter, you don't have to pass in an actual variable, you can just pass in 0, or any other valid integer. For Objects, including strings you can just pass in Nothing (Null in C#) and everything works fine. I'm not sure where the variable is stored, probably just on the stack as in any other parameter you pass in, and it disappears when the function exits.

Answer 3

While you can't actually make the out parameter optional, you could simply create an overload for the function without the out parameter, which would then take away the need to create a temporary variable.

public void DoSomething(int param1, out int param2)
{
    /* Method work here */
}

public void DoSomething(int param1)
{
    int temp;
    DoSomething(param1, out temp);
}