Q204 How can I add a method to an object?

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Q204 How can I add a method to an object?

There are two ways you add a method to an object (and it has to be an object), either by using prototype:

<script language="JavaScript"><!--

// define the myString object
function myString(value) {
    this.value = value;
}

// define the textfunc() method
function testfunc(value) {
    this.value = value;
}

// set the prototype
myString.prototype.testfunc = testfunc;

// create an instance of a myString object
var mytext = new myString('this is a test');

// alert the value propert of the mytext myString object
alert(mytext.value)

// use the myString testfunc() method
mytext.testfunc('teststring');

// alert the value propert of the mytext myString object
alert(mytext.value)

//--></script>

Or by adding a method to the object:

<script language="JavaScript"><!--

// define the myString object
function myString(value) {
    this.value = value;
    this.testfunc = testfunc;
}

// define the textfunc() method
function testfunc(value) {
    this.value = value;
}

// create an instance of a myString object
var mytext = new myString('this is a test');

// alert the value propert of the mytext myString object
alert(mytext.value)

// use the myString testfunc() method
mytext.testfunc('teststring');

// alert the value propert of the mytext myString object
alert(mytext.value)

//--></script>

Note that both approaches will not work on older browsers.

Feedback on 'Q204 How can I add a method to an object?'

July 20, 2001 at 14:11:21: Ashuthosh Bhat

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