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Specifies the function that creates an object.




The following example illustrates the use of the constructor property.

// A constructor function.
 function MyObj() {
     this.number = 1;

 var x = new String("Hi");

 if (x.constructor == String)
     document.write("Object is a String.");
 document.write ("<br />");

 var y = new MyObj;
 if (y.constructor == MyObj)
     document.write("Object constructor is MyObj.");

 // Output:
 // Object is a String.
 // Object constructor is MyObj.


The required object is the name of an object or function.

The constructor property is a member of the prototype of every object that has a prototype. This includes all intrinsic JavaScript objects except the Global and Math objects. The constructor property contains a reference to the function that constructs instances of that particular object.

See also

Other articles


  • Microsoft Developer Network: Article