How can I do a case insensitive string comparison?

Solution 1:

This is not the best practice in .NET framework (4 & +) to check equality

String.Compare(x.Username, (string)drUser["Username"], 
                  StringComparison.OrdinalIgnoreCase) == 0

Use the following instead

String.Equals(x.Username, (string)drUser["Username"], 
                   StringComparison.OrdinalIgnoreCase) 

MSDN recommends:

• Use an overload of the String.Equals method to test whether two strings are equal.
• Use the String.Compare and String.CompareTo methods to sort strings, not to check for equality.

Solution 2:

You should use static String.Compare function like following

x => String.Compare (x.Username, (string)drUser["Username"],
                     StringComparison.OrdinalIgnoreCase) == 0