Object.Equals Method (Object, Object)
Assembly: mscorlib (in mscorlib.dll)
public static boolean Equals ( Object objA, Object objB )
public static function Equals ( objA : Object, objB : Object ) : boolean
Parameters
- objA
The first Object to compare.
- objB
The second Object to compare.
Return Value
true if objA is the same instance as objB or if both are null references or if objA.Equals(objB) returns true; otherwise, false.The default implementation of Equals supports reference equality only, but derived classes can override this method to support value equality.
For reference types, equality is defined as object equality; that is, whether the references refer to the same object. For value types, equality is defined as bitwise equality. The ValueType class supports value types.
This method first determines whether both parameters are null references before calling objA.Equals(objB).
The following code example compares different objects.
using namespace System; int main() { String^ s1 = "Tom"; String^ s2 = "Carol"; Console::WriteLine( "Object.Equals(\"{0}\", \"{1}\") => {2}", s1, s2, Object::Equals( s1, s2 ) ); s1 = "Tom"; s2 = "Tom"; Console::WriteLine( "Object.Equals(\"{0}\", \"{1}\") => {2}", s1, s2, Object::Equals( s1, s2 ) ); s1 = nullptr; s2 = "Tom"; Console::WriteLine( "Object.Equals(null, \"{1}\") => {2}", s1, s2, Object::Equals( s1, s2 ) ); s1 = "Carol"; s2 = nullptr; Console::WriteLine( "Object.Equals(\"{0}\", null) => {2}", s1, s2, Object::Equals( s1, s2 ) ); s1 = nullptr; s2 = nullptr; Console::WriteLine( "Object.Equals(null, null) => {2}", s1, s2, Object::Equals( s1, s2 ) ); } /* This code produces the following output. Object.Equals("Tom", "Carol") => False Object.Equals("Tom", "Tom") => True Object.Equals(null, "Tom") => False Object.Equals("Carol", null) => False Object.Equals(null, null) => True */
import System.*;
public class MyClass
{
public static void main(String[] args)
{
String s1 = "Tom";
String s2 = "Carol";
Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", s1, s2,
System.Convert.ToString(Object.Equals(s1, s2)));
s1 = "Tom";
s2 = "Tom";
Console.WriteLine("Object.Equals(\"{0}\", \"{1}\") => {2}", s1, s2,
System.Convert.ToString(Object.Equals(s1, s2)));
s1 = null;
s2 = "Tom";
Console.WriteLine("Object.Equals(null, \"{1}\") => {2}", s1, s2,
System.Convert.ToString(Object.Equals(s1, s2)));
s1 = "Carol";
s2 = null;
Console.WriteLine("Object.Equals(\"{0}\", null) => {2}", s1, s2,
System.Convert.ToString(Object.Equals(s1, s2)));
s1 = null;
s2 = null;
Console.WriteLine("Object.Equals(null, null) => {2}", s1, s2,
System.Convert.ToString(Object.Equals(s1, s2)));
} //main
} //MyClass
/*
This code produces the following output.
Object.Equals("Tom", "Carol") => False
Object.Equals("Tom", "Tom") => True
Object.Equals(null, "Tom") => False
Object.Equals("Carol", null) => False
Object.Equals(null, null) => True
*/
import System package Equals0 { public class MyClass { public static function Main() { var s1 : String = "Tom"; var s2 : String = "Carol"; var array : Object [] = new Object[3]; array[0] = s1; array[1] = s2; array[2] = System.Object.Equals(s1, s2); Console.WriteLine("Object.Equals('{0}', '{1}') => {2}", array); s1 = "Tom"; s2 = "Tom"; array[0] = s1; array[1] = s2; array[2] = System.Object.Equals(s1, s2); Console.WriteLine("Object.Equals('{0}', '{1}') => {2}", array); s1 = null; s2 = "Tom"; array[0] = s1; array[1] = s2; array[2] = System.Object.Equals(s1, s2); Console.WriteLine("Object.Equals(null, '{1}') => {2}", array); s1 = "Carol"; s2 = null; array[0] = s1; array[1] = s2; array[2] = System.Object.Equals(s1, s2); Console.WriteLine("Object.Equals('{0}', null) => {2}", array); s1 = null; s2 = null; array[0] = s1; array[1] = s2; array[2] = System.Object.Equals(s1, s2); Console.WriteLine("Object.Equals(null, null) => {2}", array); } } } Equals0.MyClass.Main(); /* This code produces the following output. Object.Equals("Tom", "Carol") => False Object.Equals("Tom", "Tom") => True Object.Equals(null, "Tom") => False Object.Equals("Carol", null) => False Object.Equals(null, null) => True */
Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.