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navigator

Contains information about the version of Navigator in use.

Client-side object

Implemented in

Navigator 2.0
Navigator 3.0: added mimeTypes and plugins properties; added javaEnabled and
taintEnabled methods.
Navigator 4.0: added language and platform properties; added preference method.

Created by

The JavaScript runtime engine on the client automatically creates the navigator object.

Description

Use the navigator object to determine which version of the Navigator your users have, what MIME types the user's Navigator can handle, and what plug-ins the user has installed. All of the properties of the navigator object are read-only.

Property Summary

appCodeName
Specifies the code name of the browser.

appName
Specifies the name of the browser.

appVersion
Specifies version information for the Navigator.

language
Indicates the translation of the Navigator being used.

mimeTypes
An array of all MIME types supported by the client.

platform
Indicates the machine type for which the Navigator was compiled.

plugins
An array of all plug-ins currently installed on the client.

userAgent
Specifies the user-agent header.

Method Summary

javaEnabled
Tests whether Java is enabled.

plugins.refresh
Makes newly installed plug-ins available and optionally reloads open documents that contain plug-ins.

preference
Allows a signed script to get and set certain Navigator preferences.

taintEnabled
Specifies whether data tainting is enabled.

Properties

appCodeName

A string specifying the code name of the browser.

Property of

navigator

Read-only

Implemented in

Navigator 2.0

Examples

The following example displays the value of the appCodeName property:

document.write("The value of navigator.appCodeName is " +
   navigator.appCodeName)
For Navigator 2.0 and 3.0, this displays the following:

The value of navigator.appCodeName is Mozilla

appName

A string specifying the name of the browser.

Property of

navigator

Read-only

Implemented in

Navigator 2.0

Examples

The following example displays the value of the appName property:

document.write("The value of navigator.appName is " +
   navigator.appName)
For Navigator 2.0 and 3.0, this displays the following:

The value of navigator.appName is Netscape

appVersion

A string specifying version information for the Navigator.

Property of

navigator

Read-only

Implemented in

Navigator 2.0

Description

The appVersion property specifies version information in the following format:

releaseNumber (platform; country)

The values contained in this format are the following:

Examples

Example 1. The following example displays version information for the Navigator:

document.write("The value of navigator.appVersion is " +
   navigator.appVersion)
For Navigator 2.0 on Windows 95, this displays the following:

The value of navigator.appVersion is 2.0 (Win95, I)
For Navigator 3.0 on Windows NT, this displays the following:

The value of navigator.appVersion is 3.0 (WinNT, I)
Example 2. The following example populates a Textarea object with newline characters separating each line. Because the newline character varies from platform to platform, the example tests the appVersion property to determine whether the user is running Windows (appVersion contains "Win" for all versions of Windows). If the user is running Windows, the newline character is set to \r\n; otherwise, it's set to \n, which is the newline character for Unix and Macintosh.

<SCRIPT>
var newline=null
function populate(textareaObject){
   if (navigator.appVersion.lastIndexOf('Win') != -1)
      newline="\r\n"
      else newline="\n"
   textareaObject.value="line 1" + newline + "line 2" + newline
   + "line 3"
}
</SCRIPT>
<FORM NAME="form1">
<BR><TEXTAREA NAME="testLines" ROWS=8 COLS=55></TEXTAREA>
<P><INPUT TYPE="button" VALUE="Populate the Textarea object"
   onClick="populate(document.form1.testLines)">
</TEXTAREA>
</FORM>

language

Indicates the translation of the Navigator being used.

Property of

navigator

Read-only

Implemented in

Navigator 4.0

Description

The value for language is usually a 2-letter code, such as "en" and occasionally a five-character code to indicate a language subtype, such as "zh_CN".

Use this property to determine the language of the Navigator client software being used. For example you might want to display translated text for the user.

mimeTypes

An array of all MIME types supported by the client.

Property of

navigator

Read-only

Implemented in

Navigator 3.0

The mimeTypes array contains an entry for each MIME type supported by the client (either internally, via helper applications, or by plug-ins). For example, if a client supports three MIME types, these MIME types are reflected as navigator.mimeTypes[0], navigator.mimeTypes[1], and navigator.mimeTypes[2].

Each element of the mimeTypes array is a MimeType object.

See also

MimeType

platform

Indicates the machine type for which the Navigator was compiled.

Property of

navigator

Read-only

Implemented in

Navigator 4.0

Description

Platform values are Win32, Win16, Mac68k, MacPPC and various Unix.

The machine type the Navigator was compiled for may differ from the actual machine type due to version differences, emulators, or other reasons.

If you use SmartUpdate to download software to a user's machine, you can use this property to ensure that the trigger downloads the appropriate JAR files. The triggering page checks the Navigator version before checking the platform property. For information on using SmartUpdate, see Using JAR Installation Manager for SmartUpdate.

plugins

An array of all plug-ins currently installed on the client.

Property of

navigator

Read-only

Implemented in

Navigator 3.0

You can refer to the Plugin objects installed on the client by using this array. Each element of the plugins array is a Plugin object. For example, if three plug-ins are installed on the client, these plug-ins are reflected as navigator.plugins[0], navigator.plugins[1], and navigator.plugins[2].

To use the plugins array:

1. navigator.plugins[index]
2. navigator.plugins[index][mimeTypeIndex]
index is an integer representing a plug-in installed on the client or a string containing the name of a Plugin object (from the name property). The first form returns the Plugin object stored at the specified location in the plugins array. The second form returns the MimeType object at the specified index in that Plugin object.

To obtain the number of plug-ins installed on the client, use the length property: navigator.plugins.length.

plugins.refresh: The plugins array has its own method, refresh. This method makes newly installed plug-ins available, updates related arrays such as the plugins array, and optionally reloads open documents that contain plug-ins. You call this method with one of the following statements:

navigator.plugins.refresh(true)
navigator.plugins.refresh(false)
If you supply true, refresh refreshes the plugins array to make newly installed plug-ins available and reloads all open documents that contain embedded objects (EMBED tag). If you supply false, it refreshes the plugins array, but does not reload open documents.

When the user installs a plug-in, that plug-in is not available until refresh is called or the user closes and restarts Navigator.

Examples

The following code refreshes arrays and reloads open documents containing embedded objects:

navigator.plugins.refresh(true)
See also the examples for the Plugin object.

userAgent

A string representing the value of the user-agent header sent in the HTTP protocol from client to server.

Property of

navigator

Read-only

Implemented in

Navigator 2.0

Description

Servers use the value sent in the user-agent header to identify the client.

Examples

The following example displays userAgent information for the Navigator:

document.write("The value of navigator.userAgent is " +
   navigator.userAgent)
For Navigator 2.0, this displays the following:

The value of navigator.userAgent is Mozilla/2.0 (Win16; I)

Methods

javaEnabled

Tests whether Java is enabled.

Method of

navigator

Static

Implemented in

Navigator 3.0

Syntax

javaEnabled()

Parameters

None.

Description

javaEnabled returns true if Java is enabled; otherwise, false. The user can enable or disable Java by through user preferences.

Examples

The following code executes function1 if Java is enabled; otherwise, it executes function2.

if (navigator.javaEnabled()) {
   function1()
}
else function2()

See also

navigator.appCodeName, navigator.appName, navigator.userAgent

preference

Allows a signed script to get and set certain Navigator preferences.

Method of

navigator

Static

Implemented in

Navigator 4.0

Syntax

preference(prefName)
preference(prefName, setValue)

Parameters

prefName
A string representing the name of the preference you want to get or set. Allowed preferences are listed below.

setValue
The value you want to assign to the preference. This can be a string, number, or Boolean.

Description

This method returns the value of the preference. If you use the method to set the value, it returns the new value.

Security

Reading a preference with the preference method requires the UniversalPreferencesRead privilege. Setting a preference with this method requires the UniversalPreferencesWrite privilege.

For information on security in Navigator 4.0, see Chapter 7, "JavaScript Security," in the JavaScript Guide.

With permission, you can get and set the preferences shown in Table 8.2.

Table 8.2 Preferences.  
To do this... Set this preference... To...
Automatically load images

general.always_load_images
true or false

Enable Java

security.enable_java
true or false

Enable JavaScript

javascript.enabled
true or false

Enable style sheets

browser.enable_style_sheets
true or false

Enable SmartUpdate

autoupdate.enabled
true or false

Accept all cookies

network.cookie.cookieBehavior
0

Accept only cookies that get sent back to the originating server

network.cookie.cookieBehavior
1

Disable cookies

network.cookie.cookieBehavior
2

Warn before accepting cookie

network.cookie.warnAboutCookies
true or false

taintEnabled

Specifies whether data tainting is enabled.

Method of

navigator

Static

Implemented in

Navigator 3.0; removed in Navigator 4.0

Syntax

navigator.taintEnabled()

Description

Tainting prevents other scripts from passing information that should be secure and private, such as directory structures or user session history. JavaScript cannot pass tainted values on to any server without the end user's permission.

Use taintEnabled to determine if data tainting is enabled. taintEnabled returns true if data tainting is enabled, false otherwise. The user enables or disables data tainting by using the environment variable NS_ENABLE_TAINT.

Examples

The following code executes function1 if data tainting is enabled; otherwise it executes function2.

if (navigator.taintEnabled()) {
   function1()
   }
else function2()

See also

taint, untaint


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Last Updated: 10/31/97 12:32:33


Copyright 1997 Netscape Communications Corporation