How to let JavaScript know where I am on the site?
I have a single template file which renders pages that look very similar, but behave a bit different. I have a header and a few text boxes, which are filled by the template language, and there is a canvas, whose content actually differentiates the pages. It basically comes down to calling a different JavaScript function based on the page I am on, and I can't really think of an elegant (!) way to do that.
开发者_如何转开发I have a single JavaScript file that uses jQuery's document ready callback to add interactivity to the site, and also to do the drawing in the canvas. For that, I have to call a specific drawing function based on which page I am on, but I don't know it at that point.
This is certainly not impossible, I can in fact think of several different solutions, but don't really like any of these. The script file is not run through a template engine, so I can't employ any server-side logic there. I could parse the URL in the script, but this sounds like a hack to me. I could also set a variable in a script block within the template file, set a hidden field's value or something like that, but I don't think this logic belongs into the template either.
So how is this usually done?
You can give the <body> tag a "class" value, and your JavaScript code can use that (and other similar cues) to know what sorts of behaviors to add.
For example, your code could do something like:
if ($('body').hasClass('image-gallery')) {
// ... initialize image gallery code ...
}
if ($('body').hasClass('shopping-cart-summary')) {
// ... whatever ...
}
Of course it doesn't have to be just the <body> tag. Your <canvas> could also get a "class" value (and/or "data-foo" attributes) to convey information to your code.
You can embed any JavaScript you want on to a web page, built with the same server-side logic you would build the page with. So you can set global variables or (preferably) invoke functions from your .js files with parameters that contain page-specific logic. Just supply the scripts between <script> tags.
It is not clear if you want to find the page you are on, or the location in the DOM of a given page. For the former, use location.href, or location.pathname to avoid the parsing.
加载中,请稍侯......
精彩评论