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Error Console

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Revision as of 10:54, 31 October 2004
Asqueella (Talk | contribs)
(tweak the code; add a link to JS coding guidelines)
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Revision as of 02:17, 19 December 2004
Asqueella (Talk | contribs)

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-You can output information to console using the following method:+{{extdev}}
 + 
 +You can print information to JavaScript Console using the following method:
<ol> <ol>
-<li>Declare a global variable (but be sure to use an [[Dev : Javascript coding guidelines|unique identifier]]!):+<li>Declare a variable (global if you're scripting your own window or [[Dev : Javascript coding guidelines|your object's member]] if you're overlaying an existing window):
<pre>var gConsoleService = Components.classes['@mozilla.org/consoleservice;1'] <pre>var gConsoleService = Components.classes['@mozilla.org/consoleservice;1']
.getService(Components.interfaces.nsIConsoleService);</pre> .getService(Components.interfaces.nsIConsoleService);</pre>
-(note, you can also use <tt>toJavaScriptConsole()</tt> function to open JavaScript console on startup)+(note, that you can use <tt>toJavaScriptConsole()</tt> function to open JavaScript console on startup)
</li> </li>
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</ol> </ol>
-See also: [[Dev : Tips : Enabling dump|Using dump()]], [http://www.mozilla.org/projects/xpcom/using-consoleservice.html Using Console Service].+See also: [[Viewing dump() output]], [http://www.mozilla.org/projects/xpcom/using-consoleservice.html Using Console service].
 + 
 +[[Category:Development]]

Revision as of 02:17, 19 December 2004

This page is part of the extension development documentation project.

Ask your questions in MozillaZine Forums. Also try browsing example code.

Note: development documentation is in process of being moved to Mozilla Development Center (MDC).

You can print information to JavaScript Console using the following method:

  1. Declare a variable (global if you're scripting your own window or your object's member if you're overlaying an existing window):
    var gConsoleService = Components.classes['@mozilla.org/consoleservice;1']
                        .getService(Components.interfaces.nsIConsoleService);

    (note, that you can use toJavaScriptConsole() function to open JavaScript console on startup)

  2. Define a function:
    function myExt_logMessage(aMessage) {
      gConsoleService.logStringMessage('My extension: ' + aMessage);
    }
  3. Use it like here:
    myExt_logMessage("Initialized.");

See also: Viewing dump() output, Using Console service.