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How to Reliably Detect Pre-v9 Internet Explorer Versions in JavaScript?
How to Reliably Detect Pre-v9 Internet Explorer Versions in JavaScript?
Detect IE Version (Prior to v9) in JavaScript: A Comprehensive Approach
In this article, we'll explore an alternative approach to detecting pre-v9 Internet Explorer (IE) browsers using JavaScript. While the code provided in the original post may function, it has certain limitations. Let's investigate a more robust solution.
Step 1: Setting Up IE Classes
Our first step is to implement appropriate HTML classes based on the IE versions:
<!DOCTYPE html> <!--[if lt IE 7]> <html class="lt-ie9 lt-ie8 lt-ie7"> <![endif]--> <!--[if IE 7]> <html class="lt-ie9 lt-ie8"> <![endif]--> <!--[if IE 8]> <html class="lt-ie9"> <![endif]--> <!--[if gt IE 8]><!----> <html> <!----><![endif]--> <head> ...
These classes categorize different IE versions, allowing us to target them using CSS or JavaScript.
Step 2: Detecting IE and Applying JavaScript
Using jQuery, we can create a JavaScript function to recognize old IE browsers and apply the necessary actions:
(function ($) {
"use strict";
// Detecting IE
var oldIE;
if ($('html').is('.lt-ie7, .lt-ie8, .lt-ie9')) {
oldIE = true;
}
if (oldIE) {
// Here's your JS for IE..
} else {
// ..And here's the full-fat code for everyone else
}
}(jQuery));Addressing Concerns
To address your concerns:
- Useragent String Forgery: Even though users can forge their useragent, this approach still provides a reliable indication of IE browser versions.
- Feature-Support Sniffing: While feature-support sniffing is generally preferred, it would be inefficient in this case where specific features are already known to be supported or not by different browser versions.
- IE Versions 1 or >= 20: Our code intentionally excludes these versions from the "badBrowser" detection, acknowledging the potential risks.
- Conditional Comments: IE 10 and later do not support conditional comments, making them an ineffective solution.
Conclusion
This JavaScript-based approach provides a flexible and accurate way to detect pre-v9 IE browsers. By using CSS classes and jQuery, we can seamlessly implement specific actions based on browser versions, ensuring a more consistent user experience.
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