Most performant way of checking empty strings in C#

Question

What is the best way for checking empty strings (I'm not asking about initializing!) in C# when considering code performance?(see code below)

string a;

// some code here.......


if(a == string.Empty)

or

if(string.IsNullOrEmpty(a))

or

if(a == "")

any help would be appreciated. :)

Answer 1

Do not compare strings to String.Empty or "" to check for empty strings.

Instead, compare by using String.Length == 0

The difference between string.Empty and "" is very small. String.Empty will not create any object while "" will create a new object in the memory for the checking. Hence string.empty is better in memory management. But the comparison with string.Length == 0 will be even faster and the better way to check for the empty string.