C#-Isnullorempty

IsNullOrEmpty() is a string method. It is used to check whether the specified string is null or an Empty string. A string will be null if it has not been assigned a value. A string will be empty if it is assigned “” or String.Empty (A constant for empty strings)

Syntax:

public static bool IsNullOrEmpty(String str)  

Explanation: This method will take a parameter which is of type System.String and this method will returns a boolean value. If the str parameter is null or an empty string (“”) then return True otherwise return False.

Example:

Input : str  = null         // initialize by null value
        String.IsNullOrEmpty(str)
Output: True

Input : str  = String.Empty  // initialize by empty value
        String.IsNullOrEmpty(str)
Output: True