Microsoft® JScript™ prototype Property | Language Reference Version 2

See Also Applies To

##### Description

> Contains a reference to the prototype for a class of objects.

##### Syntax

> objectname.prototype

> The objectname argument is the name of an object.

##### Remarks

> Use the prototype property to provide a base set of functionality to a class of objects. New instances of an object "inherit" the behavior of the prototype assigned to that object.

> For example, say you want to add a method to the Array object that returns the value of the largest element of the array. To do this, declare the function, add it to Array.prototype, and then use it.

> >     function array_max( )
> >     {
> >       var i, max = this[0];
> >       for (i = 1; i < this.length; i++)
> >       {
> >          if (max < this[i])
> >     	     max = this[i];
> >       }
> >       return max;
> >     }
> >     Array.prototype.max = array_max;
> >     var x = new Array(1, 2, 3, 4, 5, 6);
> >     var y = x.max( );

> After this code is executed, y contains the largest value in the array x, or 6.

> All intrinsic JScript objects have a prototype property that is read-only. Functionality may be added to the prototype, as in the example, but the object may not be assigned a different prototype. However, user-defined objects may be assigned a new prototype.

> The method and property lists for each intrinsic object in this language reference indicate which ones are part of the object's prototype, and which are not.

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