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toString Redirect 4

Summary

The toString() method returns a string representing the specified Error object.

Syntax

e.toString();

Description

The Error object overrides the Object.prototype.toString() method inherited by all objects.  Its semantics are as follows (assuming Object and String have their original values):

Error.prototype.toString = function()
{
  "use strict";

  var obj = Object(this);
  if (obj !== this)
    throw new TypeError();

  var name = this.name;
  name = (name === undefined) ? "Error" : String(name);

  var msg = this.message;
  msg = (msg === undefined) ? "" : String(msg);

  if (name === "")
    return msg;
  if (msg === "")
    return name;

  return name + ": " + msg;
};

Example

var e = new Error("fatal error");
print(e.toString()); // "Error: fatal error"

e.name = undefined;
print(e.toString()); // "Error: fatal error"

e.name = "";
print(e.toString()); // "fatal error"

e.message = undefined;
print(e.toString()); // "Error"

e.name = "hello";
print(e.toString()); // "hello"

Specifications

Specification Status Comment
ECMAScript 1st Edition. Standard Initial definition.
Implemented in JavaScript 1.1
ECMAScript Language Specification 5.1th Edition (ECMA-262) Standard  
ECMAScript Language Specification 6th Edition (ECMA-262) Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

Document Tags and Contributors

 Last updated by: Sheppy,