Error object

Availability

Flash Player 7.

Description

Instances of the Error object are generated ("thrown") when an error occurs. Typically, instances of the Error object are thrown by the throw statement from within a try..catch..finally block, as shown below.

try {
	// In try {} code block, add ActionScript code to execute
	// If an error occurs, throw an instance of the Error object
	if(someErrorOccured) {
		throw new Error();
	}
} catch (e) {
	// ActionScript to handle error
}

You can also throw custom error objects. To do this, you create a constructor function for the custom error object, and throw a new instance of that object from within the try{} code block.

function CustomErrorObject{
	// constructor for CustomErrorObject
}
try {
	if(errorCondition) {
		throw new CustomErrorObject();
	}
} catch (e) {
	// Determine the type of error that occurred:
	if(e instanceof customErrorObject) {
		// handle custom error condition
	}
}

Method summary for the Error object

Method Description
Error.toString() Returns the string representation of an Error object.

Property summary for the Error object

Property Description
Error.message A string that contains an error message associated with a particular error.
Error.name The name or exception type of an error.

Constructor for the Error object

Availability

Flash Player 7.

Usage

new Error([message])

Parameters

message A string associated with the Error object.

Returns

An instance of an Error object.

Description

Constructor; creates a new instance of the Error object. If message is specified, its value is assigned to the object's Error.message property. Typically, new instances of the Error object are thrown by a throw statement and handled ("caught") by a catch statement.

Example

The following example demonstrates how to throw an error by using the throw statement.

var sock = new XMLSocket();
try {
	// Try to connect to server, and throw an exception if it fails.
	if (!sock.connect("www.yourserver.com", 8080)) {
		throw new Error("Couldn't connect socket.");
	}
	// Otherwise, work with socket object normally...
	//
} catch (error) {
	if(error.message == "Couldn't connect socket") {
		// Inform user that connection failed
		status_txt.text = "Connection failed.";
	}	
}

See also

throw, try..catch..finally