Java Script Error Message
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Javascript Error Message Example
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users have encountered the annoying JavaScript error at some stage. This happens when a script in a web page contains an error or fails to execute correctly. Exactly what happens depends on the browser and type of error, but in most cases some sort of error notification will be displayed. The Error Message In Internet Explorer's default http://www.mediacollege.com/internet/javascript/basic/error.html setting, a small warning icon appears in the status bar like the one pictured left. Double-click this icon to display a window with the complete error message. The complete error message looks something like this: Note: If you see a https://codex.wordpress.org/Using_Your_Browser_to_Diagnose_JavaScript_Errors less detailed version of this window, click the "Show Details" button. You can choose to have this error window appear automatically whenever an error occurs. This could be annoying for general surfing, but it is very useful when writing your own error message JavaScript. This is because the error message always lets you know when something is wrong with your code, and even better, it usually tells you exactly where in the HTML document the problem lies (in the above example, line 71 character 1). What to Do When You See an Error If you are visiting a website which shows an error, you obviously can't fix it but if you're feeling generous you might like to contact the webmaster and let them know. You script error message can still view the page (disabling automatic error messages will make it easier), but whatever the script was supposed to do won't work. This may or may not effect on the functionality of the page. If you are the webmaster, you need to understand what the error message is telling you and fix it. Keep reading.... How to Fix JavaScript Errors There are two types of JavaScript error: Syntax Error: Occurs when there is a mistake in the way the code is written; for example, a typo or missing character. Runtime error: Occurs when the script is unable to complete its instructions; for example, if a specified object cannot be found. Syntax Error The function below contains an error and will result in the error message as pictured. In this case the message tells you that a closing parenthesis is missing. function showAlert() { alert('Hello World!'; } Not all error messages are as clear as this but once you've seen a few (and you will see a few!) you'll start to recognise what they mean. Runtime Error The function below is constructed correctly and will run with no problems as long as the variable something can be found (remember that a text string without quotes is assumed to be a variable). If this variable is not defined an error will occur. function showAlert2() { alert(something); } Note: Syntax error messages appear as soon as the page loads, even if the error is inside
the new WordPress Code Reference! Using Your Browser to Diagnose JavaScript Errors If you're experiencing issues with your interactive functionality this may be due to JavaScript errors or conflicts. For example, your flyout menus may be broken, your metaboxes don't drag, or your add media buttons aren't working. In order to formulate your support request it helps the team to know what the JavaScript error is. This guide will show you how to diagnose JavaScript issues in different browsers. Contents 1 Step 1: Try Another Browser 2 Step 2: Enable SCRIPT_DEBUG 3 Step 3: Diagnosis 3.1 Firefox 3.2 Internet Explorer 3.3 Chrome 3.4 Safari 3.5 Opera 4 Step 4: Reporting Step 1: Try Another Browser To make sure that this is a JavaScript error, and not a browser error, first of all try opening your site in another browser. if the site is not having the same issue in the new browser you know that the error is browser specific if the site is having the same error it is not an error that is specific to one browser Make note of any browsers you are experiencing the error in. You can use this information when you are making a support request. Step 2: Enable SCRIPT_DEBUG You need to turn on script debugging. Open wp-config.php and add the following line before "That's all, stop editing! Happy blogging". define('SCRIPT_DEBUG', true); Check to see if you are still having an issue. Issue is fixed - turn off script debugging and report the issue on the support forum, telling the volunteers that you turned on script debugging and it solved the problem. Issue persists - proceed to Step 3. Step 3: Diagnosis Now that you know which browsers you are experiencing issues in you can start to diagnose the issue. Firefox 1. Open the Console Go to the screen where you are experiencing the error. In Firefox, nav