what Difference between this commands in c#
string text= " ";
IsNullOrWhiteSpace is a convenience method that is similar to the following code, except that it offers superior performance:
return String.IsNullOrEmpty(value) || value.Trim().Length == 0;
White-space characters are defined by the Unicode standard. The IsNullOrWhiteSpace method interprets any character that returns a value of true when it is passed to the Char.IsWhiteSpace method as a white-space character.