string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)

Question

Is use of string.IsNullOrEmpty(string) when checking a string considered as bad practice when there is string.IsNullOrWhiteSpace(string) in .NET 4.

Answer 1

What about this for a catch all...

if (string.IsNullOrEmpty(x.Trim())
{
}

This will trim all the spaces if they are there avoiding the performance penalty of IsWhiteSpace, which will enable the string to meet the "empty" condition if its not null.

I also think this is clearer and its generally good practise to trim strings anyway especially if you are putting them into a database or something.