?? Coalesce for empty string?

Question

Something I find myself doing more and more is checking a string for empty (as in \"\" or null) and a conditional operator.

A current example:

Answer 1

I simply use a NullIfEmpty extension method which will always return null if the string is empty allowing ?? (Null Coalescing Operator) to be used as normal.

public static string NullIfEmpty(this string s)
{
    return string.IsNullOrEmpty(s) ? null : s;
}

This then allows ?? to be used as normal and makes chaining easy to read.

string string1 = string2.NullIfEmpty() ?? string3.NullIfEmpty() ?? string4;