spacer
Yehuda Shiran March 10, 2001
Checking for a Certain Property
Tips: March 2001

Yehuda Shiran, Ph.D.
Doc JavaScript

Developer News
Microsoft Shows Off Silverlight 4, IE9 Plans
Metasploit Expands Vulnerability Test Framework
HyperCard Reborn?

Use the hasOwnProperty() method to find out if an object has a certain property you are interested in. The hasOwnProperty() is a method of the Object object, and thus all objects inherit it (all objects are subclasses of the Object object). The following code checks if the object Ken of the Employee subclass has a manager. Try it, it should give true:

function Employee() {
  this.dept = "HR";
  this.manager = "John Johnson";
}

function printProp() {
  var Ken = new Employee();
  alert(Ken.hasOwnProperty("manager"));
}


People who read this tip also read these tips:

Look for similar tips by subject:

internet.commediabistro.comJusttechjobs.comGraphics.com

Search:

WebMediaBrands Corporate Info

Legal Notices, Licensing, Permissions, Privacy Policy.
Advertise | Newsletters | Shopping | E-mail Offers | Freelance Jobs

webref The latest from WebReference.com Browse >
Rolling Out Your Own HTML Application Version Control · HTML 5: Client-side Storage · Working with Ajax Server Extensions
Sitemap · Experts · Tools · Services · Email a Colleague · Contact FREE Newsletters 
 The latest from internet.com
Wi-Fi Product Watch, November 2009 · Chip Market Recovering From '08 Collapse · Low-Cost Tools to Kickstart Your New Business