Javascript object Object - Properties and Methods
Description
Parent of all JavaScript objects. it is a primitive javascript object type.
Can be created by Object constructor, for example, new object().
Javascript Objects Property
| Name | Description | Version |
|---|---|---|
| constructor | Specifies the function that creates an object's prototype. | Implemented in JavaScript 1.2 |
| prototype | Use to add new properties and methods to an object. | Implemented in JavaScript 1.2 |
Javascript Objects Methods
| Name | Description | Version |
|---|---|---|
| tosource | Use to get a string representation (source code) of the object. | Implemented in JavaScript 1.2 |
| tostring | Rrepresent the source code of the specified object. | Implemented in JavaScript 1.2 |
| valueof | Returns the primitive value of the specified object. | Implemented in JavaScript 1.2 |
| watch | Use to watch a particular property of an object. | Implemented in JavaScript 1.2 |
| unwatch | Use to remove a watch point for a particular property set by the watch() method. | Implemented in JavaScript 1.2 |
JavaScript constructor Property: Object
Specifies the function that creates an object's prototype. Syntax Object: The name of the object (Required). Example: The following web document demonstrates how the constructor property can be used. View the example in the browser JavaScript prototype Property: Object The prototype property is used to add new properties and methods to an object. Syntax Example: The following web document demonstrates how the prototype property can be used. JavaScript toSource Method: Object The toSource() method is used to get a string representation (source code) of the object. Note that toSource for Object object is non-standard. Syntax Parameters None Example: In the following web document tosource() method returns the source code of the given object. Supported Browser JavaScript toString Method: Object The toString() method returns a string, representing the source code of the specified object. Syntax Parameters None Example: In the following web document tostring() method returns the string representation of a given number. View the example in the browser Supported Browser JavaScript valueOf Method: Object The valueOf() method returns the primitive value of the specified object. Syntax Parameters None Example: In the following web document valueOf() method is used to get the primitive value of a number object. View the example in the browser Supported Browser JavaScript watch() Method: Object The watch() method is used to watch a particular property of an object. If the property is changed then watch() method turns on and runs a function. Syntax
Parameters prop: The name of a property of the object. Example: The following web document demonstrates how the watch() method can be used. View the example in the browser Supported Browser JavaScript unwatch() Method: Object The unwatch() method of the object is used to remove a watchpoint for a particular property set by the watch() method. Syntax Parameters prop: The name of a property of the object. Example: The following web document demonstrates how the unwatch() method can be used. View the example in the browser >Supported Browser See also: Previous: JavaScript valueOf Method: Number ObjectObject.constructor
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Object constructor Property : Example-1</title>
</head>
<body><h1 style="color: red">JavaScript Object constructor Property</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
myarray = new Array("Orange", "Apple", "Banana", "Cherry", "Mango");
if(myarray.constructor == Array){
document.write("Object is created...");
}
//]]>
</script>
</body>
</html>
object.prototype.property
object.prototype.method
View the example in the browser
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript object prototype property : Example-1</title>
</head>
<body><h1 style="color: red">JavaScript object prototype property</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
var mynum = new Number();
function square(x,y){
var numsqr;
numsqr = (x*x + 2*x*y + y*y);
return numsqr;
}
Number.prototype.sqrcal = square;
document.write("sqaure of (4+3) is " +mynum.sqrcal(4,3) + "<br>");
//]]>
</script>
</body>
</html>
toSource()
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Object object - toSource() method example</title>
</head>
<body>
<h1 style="color: red">JavaScript object : toSource() method</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
function student(name,class,rollno,sex)
{
this.name = name
this.class = class
this.rollno = rollno
tis.sex = sex
}
student1 = new student('Subhasish Chatterjee','VI',10,'M')
//Calling the toSource method of student1 displays the source which defines in the object.
document.write(student1.toSource());
//]]>
</script>
</body>
</html>
Internet Explorer 7
Firefox 3.6
Google Chrome 7
Safari 5.0.1
Opera 10
Yes
Yes
Yes
Yes
Yes
Object.toString()
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript object - toString() method example</title>
</head>
<body>
<h1 style="color: red">JavaScript object : toString() method</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
<script type="text/javascript">
function Student(name,standard,rollno,sex) {
this.name=name;
this.standard=standard;
this.rollno=rollno;
this.sex=sex;
}
theStudent = new Student("Subhasish Chatterjee","VI",10,"Male");
document.write(theStudent.toString());
</script>
//]]>
</script>
</body>
</html>
Internet Explorer 7
Firefox 3.6
Google Chrome 7
Safari 5.0.1
Opera 10
Yes
Yes
Yes
Yes
Yes
valueOf()
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript object - valueOf() method example</title>
</head>
<body>
<h1 style="color: red">JavaScript object : valueOf() method</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
var x = Number(201);
document.write(x.valueOf());
//]]>
</script>
</body>
</html>
Internet Explorer 7
Firefox 3.6
Google Chrome 7
Safari 5.0.1
Opera 10
Yes
Yes
Yes
Yes
Yes
watch(prop, handler)
handler: A function to call.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Object - watch () method example</title>
</head>
<body>
<h1 style="color: red">JavaScript Object : watch() method</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
o = {x:10}
o.watch("x",
function (id,oldvalue,newvalue) {
document.writeln("o." + id + " changed from "
+ oldvalue + " to " + newvalue+"<br />")
return newvalue
})
o.x = 20
o.x = 30
o.x = 40
//]]>
</script>
</body>
</html>
Internet Explorer 7
Firefox 3.6
Google Chrome 7
Safari 5.0.1
Opera 10
Yes
Yes
Yes
Yes
Yes
unwatch(prop)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>JavaScript Object - unwatch () method example</title>
</head>
<body>
<h1 style="color: red">JavaScript Object : unwatch() method</h1>
<hr />
<script type="text/javascript">
//This is done to make the following JavaScript code compatible to XHTML. <![CDATA[
a = {x:10}
a.watch("x",
function (id,oldvalue,newvalue) {
document.write("a." + id + " changed from "
+ oldvalue + " to " + newvalue+"<br />")
return newvalue
})
a.x = 20
a.x = 30
a.x = 40
// start unwatch from here
a.unwatch('x')
a.x = 100
document.write("Current value of x is : "+a.x)
//]]>
</script>
</body>
</html>
Internet Explorer 7
Firefox 3.6
Google Chrome 7
Safari 5.0.1
Opera 10
Yes
Yes
Yes
Yes
Yes
JavaScript Core objects, methods, properties.
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JavaScript: Regular Expression
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