isPrototypeOf Method (Windows Scripting - JScript)

 

Returns a Boolean value indicating whether an object exists in another object's prototype chain.

Syntax

object1.isPrototypeOf(object2)

Arguments

• object1
  Required. Instance of an object.

• object2
  Required. Another object whose prototype chain is to be checked.

Remarks

The isPrototypeOf method returns true if object2 has object1 in its prototype chain. The prototype chain is used to share functionality between instances of the same object type. The isPrototypeOf method returns false when object2 is not an object or when object1 does not appear in the prototype chain of the object2.

The following example illustrates the use of the isPrototypeOf method.

function test(){
  var re = new RegExp();                        //Initialize variable.
  return (RegExp.prototype.isPrototypeOf(re));  //Return true.
}

Requirements

Version 5.5

Applies To: Object Object (Windows Scripting - JScript)

See Also

isFinite Method (Windows Scripting - JScript)