Why can't an out parameter have a default value?

Question

Currently when trying to do something in a method that takes an out parameter, I need to assign the value of the out parameter in the method body, e.g.

publi         


        

Answer 1

I appreciate this isn't exactly answering the original question, but I'm unable to contribute to the comments. I had the same question myself so found myself here.

Since C#7 now allows out parameters to effectively be variable declarations in the calling scope, assigning a default value would be useful.

Consider the following simple method:

private void ResolveStatusName(string statusName, out string statusCode)
    {
        statusCode = "";
        if (statusName != "Any")
        {
            statusCode = statusName.Length > 1
                ? statusName.Substring(0, 1)
                : statusName;
        }
    }

It felt intuitive to modify it like so:

 private void ResolveStatusName(string statusName, out string statusCode = "")
    {
        if (statusName != "Any")
        {
            statusCode = statusName.Length > 1
                ? statusName.Substring(0, 1)
                : statusName;
        }
    }

The intention was to not only declare the statusCode value, but also define it's default value, but the compiler does not allow it.