May 5, 2001 - Suppressing Error Messages | WebReference

May 5, 2001 - Suppressing Error Messages

Yehuda Shiran May 5, 2001
Suppressing Error Messages
Tips: May 2001

Yehuda Shiran, Ph.D.
Doc JavaScript

Suppressing error messages is a controversial issue in all programming languages. That's a classical programmer dilemma. Should a program screams when a bug is found, or should the bug go unnoticed? Since this is a "religious" issue, it is left for your own decision. What is not questionable is the need for error messages during early development stages of the program. In this phase, you probably need the error messages for debugging your new script.

FlashSound JavaScript API lets you choose whether to suppress error message or not, with the muteErrorMsg property of the FlashSound object. Notice the double negative here. In order to suppress error message, you need to set this property to false. Set it to true during the debugging phase. The default setting is true, i.e. error messages are suppressed by default.

As a reminder, in order to sonify your page, follow this recipe:

flashsound.js in the HEAD section. Download.
  • Create a flashsound object in the
    • HEAD section.
  • Embed your SWF file in the
    • BODY section.
  • Create an anchor tag and set the
    • onmouseover event handler to the TGotoAndPlay() method.

    The following JavaScript code include an error, because the variable a is not defined:

    <SCRIPT LANGUAGE="JavaScript">
  FlashSound.muteErrorMsg = a;  
</SCRIPT>

    We can choose to get or suppress an error message for this JavaScript error. The following script will suppress the error:

    <SCRIPT LANGUAGE="JavaScript">
  FlashSound.muteErrorMsg = true;
  FlashSound.muteErrorMsg = a;  
</SCRIPT>

    And the following script will reveal the error:

    <SCRIPT LANGUAGE="JavaScript">
  FlashSound.muteErrorMsg = false;
  FlashSound.muteErrorMsg = a;  
</SCRIPT>

    Click the following two links to see a demo for each of these two file:

    Reveal Error Messages

    Suppress Error Messages

    Here is the source code for the file that reveals the error:

    <HTML>
<HEAD>
<SCRIPT SRC="flashsound.js"></SCRIPT>
</HEAD>
<BODY>
<SCRIPT LANGUAGE="JavaScript">
  FlashSound.muteErrorMsg = false;
  FlashSound.muteErrorMsg = a;  
</SCRIPT>
</BODY>
</HTML>

    And here is the source code for the file that suppress the error:

    <HTML>
<HEAD>
<SCRIPT SRC="flashsound.js"></SCRIPT>
</HEAD>
<BODY>
<SCRIPT LANGUAGE="JavaScript">
  FlashSound.muteErrorMsg = true;
  FlashSound.muteErrorMsg = a;  
</SCRIPT>
</BODY>
</HTML>

    Here is a link you can use to download flashsound.js.

    Download flashsound.js