Object.ReferenceEquals() Method in C#

Object.ReferenceEquals() Method is used to determine whether the specified Object instances are the same instance or not. This method cannot be overridden. So, if a user is going to test the two objects references for equality and is not sure about the implementation of the Equals method, then he can call the ReferenceEquals method.

Syntax: public static bool ReferenceEquals (object ob1, object ob2); 

Parameters: 

ob1: It is the first object to compare. 

ob2: It is the second object to compare. 

Return Value: This method returns true if ob1 is the same instance as ob2 or if both are null otherwise, it returns false.

Below programs illustrate the use of Object.ReferenceEquals() Method: 

Example 1: 

null is equal to null

Example 2: 

System.Object is not equal to 
System.Object is equal to System.Object
System.Object is not equal to 

Note: Here, null will never be printed in the output. Important Points:

• If both ob1 and ob2 represent the same instance of a value type, then this method nevertheless returns false.
• If ob1 and ob2 are strings, then this method will return true if the string is interned because this method will never perform a test for value equality.

Reference:

• https://learn.microsoft.com/en-us/dotnet/api/system.object.referenceequals?view=netcore-2.1