IsNullOrEmpty and IsNullOrWhiteSpace

 

Both methods are part of the System namespace and are commonly used in string validation scenarios.

In C#, the String.IsNullOrEmpty and String.IsNullOrWhiteSpace methods are used to check if a string is null, empty, or consists only of white-space characters.

 

String.IsNullOrEmpty is Used to Check Strings is null or Empty

String.IsNullOrWhiteSpace is Used to Check string is null,Empty and Whitespaces







Example String	String.IsNullOrEmpty	String.IsNullOrWhiteSpace
“”	true	true
null	true	true
“         ”	false	true
"\n\t"	false	True
“Hello”	false	false




String.IsNullOrEmpty

• Purpose: Checks if a string is either null or an empty string ("").
• Syntax: public static bool IsNullOrEmpty(string value)

String.IsNullOrWhiteSpace

• Purpose: Checks if a string is null, empty, or consists only of white-space characters (such as spaces, tabs, or newlines).
• Syntax: public static bool IsNullOrWhiteSpace(string value)

 

Key Differences

• Whitespace Check: IsNullOrWhiteSpace is more comprehensive as it also checks for white-space characters in addition to null and empty strings,
• while IsNullOrEmpty only checks for null and empty strings.

 

Use Cases:

• Use IsNullOrEmpty when you only need to check if a string is null or empty.
• Use IsNullOrWhiteSpace when you need to check if a string is null, empty, or contains only white-space characters.