Returns a Boolean value indicating whether an object has a property with the specified name.

object.hasOwnProperty(proName)

Arguments

object

Required. Instance of an object.

proName

Required. String value of a property name.

Remarks

The hasOwnProperty method returns true if object has a property of the specified name, false if it does not. This method does not check if the property exists in the object's prototype chain; the property must be a member of the object itself.

Example

In the following example, all String objects share a common split method. The following code will print false and true.

var s = new String("JScript");
print(s.hasOwnProperty("split"));
print(String.prototype.hasOwnProperty("split"));

Requirements

Version 5.5

See Also

in Operator

Applies To: Object Object