Get parameters of .js file - javascript

I have a javascript file that I reference in HTML with standard <script src="foo.js?param"></script>. In the file I want to distinguish e.g. loading the file with foo.js from foo.js?auto and foo.js?noauto=true, but not if the file is renamed to bar.js and referenced with the same parameter. How can I accomplish this, preferably not using any framework?

Take a look a scriptaculous' approach:
var js = /scriptaculous\.js(\?.*)?$/;
$$('head script[src]').findAll(function(s) {
return s.src.match(js);
}).each(function(s) {
var path = s.src.replace(js, ''),
includes = s.src.match(/\?.*load=([a-z,]*)/);
(includes ? includes[1] : 'builder,effects,dragdrop,controls,slider,sound').split(',').each(
function(include) { Scriptaculous.require(path+include+'.js') });
});
I think it runs through all script elements and finds the reference to itself, and then parses that URL.

If you want to do it reliably, then you need to provide different JS for each URL. You could generate it with a server side script.
If you want to do it in pure JS, then you can getElementsByTagName('script') and assume that last script is the one that matched (it might not be, e.g. if script elements are being added using DOM after the page has loaded).

Related

How to place other JavaScript file links in a Javascript? [duplicate]

This question already has answers here:
How do I include a JavaScript file in another JavaScript file?
(70 answers)
Closed 6 years ago.
I have a bunch of JavaScript links at the bottom of one of my HTML template. I want to create a separate JavaScript file that will only contain all the source links in it.
So instead of cluttering my template footer I want all the links in one JavaScript file. How can I achieve that?
What I'm really asking is how I can get a similar effect as the CSS #import functionality for JavaScript.
And if that is not possible can I place a block of HTML at the footer of my template from a different HTML file?
You could do this with ajax but an easy way is to just append them with jquery
$('.div').append('<script src="myscript.js"></script>');
hope that helps
You can create a seperate js file and a object in it. This object can have multiple keys and their value will these links. Return this object from the file
Hope this snippet will be useful
linkFile.js
var AllLinks = function(){
var _links ={};
_links.keyOne ="link1";
_links.keyTwo ="link2";
return {
links:_links
}
}
Also include this file using script tag
In other file you can retrieve this value as
AllLinks.links.keyOne & so on
Have an array that holds the link to your script files and then you have two options either to use $.getScript() to load each one Or by building an HTML out of it and appending it to your head or body tag. I prefer head tag to keep all the scripts and css files.
Your array of script files
var JsFiles = ["script1.js","script2.js","script3.js","script4.js"];
First approach using $.getScript()
JsFiles.each(function(i,v){
$.getScript(JsFiles[i], function( data, textStatus, jqxhr){
console.log( textStatus ); // Success
});
});
Disadvantage of the above approach is that the getScript makes a async calls to your script files that means if the script2.js is dependent on the script1.js (for example if script1.js is some plugin file which use initialize in script2.js) Then you will face issues.
To overcome you might have to then use Promises or write a callback on each getScript success function which will trigger next script load and so on..
If the order of the script loading is not important then above approach is good to go.
Second approach by building HTML
var scriptTags ="";
JsFiles.each(function(i,v){
scriptTags += "<script src='"+ JsFiles[i] +"'></script>";
});
$('head').append(scriptTags);
Good thing about this approach is that the script files will now load synchronously and you will not face the dependency problem. But make sure the independent files start from first and the dependent files come at last.

In my asp.net-mvc file, how can I move my javascript to a seperate js file?

I have a bunch of javascript inside my view and its getting quite large so I want to move it to a separate js file. The one issue I have is that I have this line:
var tags = <%= new JavaScriptSerializer().Serialize(Model.Tags) %>;
which I obviously can't just copy over since it has the server side asp.net-mvc tags. What is the recommended way to deal with that:
Keep this one function inside the aspx page and have the javascript from the seperate js file call that function?
Other??
What you could do is have a JavaScript object contain all the information you get from the controller and pass it through a javascript function which is located in the external javascript file. You can also pass other information through the options variable.
Example:
var options = {
tags: <%= new JavaScriptSerializer().Serialize(Model.Tags) %>
};
initPage(options);
Usage:
function initPage(options) {
console.log(options.tags);
}
This depends a lot on the way you want to use it and the level of repeating.
Some thoughts:
The tags are static. Then I guess then don't really need to be in the model. So you can move them into a new Controller action which outputs the scipt. You can call this action in the <script> part of your view.
The tags are changing very frequently (maybe even at every page load). Then there is no gain in moving this in a separate script file.
If you set up your javascript file with proper closures, you can expose a property (or better yet, a parameter to the object/method) with which to pass that information along when you call that function.
Your Javascript would need to be something like this:
var JsFile = (function() {
var tags;
// list all of your methods here.
return {
var setTags = function(_tags) {
tags = _tags;
}
};
})();

Insert JavaScript data chunk (JSON) into an HTML page

I need to include a JavaScript object (JSON) in my HTML page.
JSON is rendered at the same time page HTML is rendered on server. Data is not retrieved using AJAX call.
I can think of two ways of doing this, and looking for feedback and recommendations.
What are good practices for passing JavaScript (JSON) blob with a page?
Option 1
HTML:
<script type='text/javascript'>
var model = { <JSON> };
</script>
.js:
function doSomething() { <use this.model here> }
Option 2
HTML:
<script type='text/javascript'>
loadModel({<JSON>});
</script>
.js (included at the top of the html file):
var model = null;
function loadModel(model) { this.model = model; }
function doSomething() { <use this.model here> }
Variation
Instead of including JSON in HTML, JSON can be stored in a separate .js file. Any comments on doing so?
Option 1 lets you include .js file anywhere, and including it at the bottom of the page makes it render faster (good thing), but since JavaScript renders the model on the page, this makes it a moot point. Still not depending on the location of the .js inclusion makes it less error prone.
Also R# complains (reasonably) about model being uninitialized.
Option 2 feels better (it encapsulate details better, for one), but .js must be included before call to loadModel.
I have seen and done both ways, but didn't notice any significant advantages of one way over the other.
Server platform should be irrelevant, but it is IIS 7.5/ASP.NET MVC 3/Razor
Forget your two suggestions - both are extremely vulnerable to XSS. NEVER PUT UNTRUSTED TEXT IN A SCRIPT TAG.
Instead, use the owasp recommendation.
Stick your (HTML encoded) JSON in the DOM like so:
<div id="init_data" hidden>
<%= html_escape(data.to_json) %>
</div>
Then read it in JavaScript like so:
// external js file
var dataElement = document.getElementById('init_data');
// decode and parse the content of the div
var initData = JSON.parse(dataElement.textContent);
There would be ever so slightly more overhead with option two. As you have the overhead of a function call, and an extra variable (your parameter), which will be allocated and deallocated.
As you said, there is little advantage/disadvantage to either way.
Can you use jQuery? Then you can use the DOM ready event instead of including javascript in your HTML.
EDIT:
Hmm, in that case you could include the JSON inside a hidden element when the page is generated. Then inside the DOM ready event you could read and parse it from the page using jQuery.
Another alternative might be to use HTML 5 data attributes and including the data in one of those.
If it were me I'd probably just use an ajax call since it is easier and seems a little cleaner.

How to get texts from Resx to be used in Javascript?

We are building large ASP.NET applications for the intranet use in multiple languages/cultures. We utilize the Globalization with RESX files and use GetResourceText on the server side to get the localized texts.
Lately we are doing more and more client side logic with JQuery.
How do I get the RESX texts to be used in Javascript?
e.g. texts used for validation, dynamic messages etc.
All our Javascripts are in .JS files, we do not want to mix HTML in the ASPX page and Javascript blocks.
Thanks for your help.
Unfortunately, in an external JS file the server side code is not being processed by the server. However I have seen a workaround where you can set your translated values in hidden fields on the page - this way your javascript will be able to read the values in.
For example:
<%-- This goes into your page --%>
<input type="hidden" id="translatedField" name="translatedField" value="<%=Resources.Resources.translatedText %>" />
and use this inside your javascript file:
// This is the js file
$(document).ready(function() {
alert($("#translatedField").attr("value"));
});
You will be able to separate the values and still see it in your external JS file.
There is also another workaround that creates a .aspx file that only outputs Javascript instead of HTML. Check out the link below:
Using server side method in an external JavaScript file
Always separate functionality from human readable strings.
If you're creating jQuery-plugins you should be able to pass an array of localized strings as parameter when you call your different jQuery functions. The array could be defined as inline javascript directly on the page calling the different jQuery plugins or you could load the from external resource in the format /scripts/localization/strings.js?ci=en-US and register a Generic ASP.Net Handler in web.config that would respond to scripts/localization/strings.js
The DatePicker control is a fine example of how to localize text for the jQuery datepick control - this js file is dynamically created from resource files (resx) and when included on a page it will make sure the calendar control will have danish text.
Create a HttpHandler (.ashx file), and return JSON with your text resource strings.
You may also "publish" it to global namespace, i.e.
Response.Write("window.Resources=");
Response.Write((new JavaScriptSerializer()).Serialize(strings));
set up HTML like:
<script src="Resx.ashx?lang=en-US" />
<button class="LogoutButtonResourceId OtherButtonClasses">(generic logout text)</button>
<a href="#"><span class="SomeLinkTextResourceId OtherClasses">
(generic link text)
</span></a>
and apply texts like this:
$(document).ready(function() {
for(var resId in Resources){
$("."+resId).html(Resources[resId]);
}
});
If you don't want to use ASP.NET to generate your main JavaScript, here are two other options:
Use ASP.NET to generate a script file that contains variable-to-string assignments, such as var mystring = 'my value';. Your main script would then reference the localized text with variables names rather than as embedded values. If that's still too "dirty" for you, you could encode the strings as JSON rather than as variable assignments, using an HttpHandler rather than straight .aspx.
Have your JavaScript code issue an Ajax call to retrieve an array or list of localized strings from the server. The server-side part of the call would retrieve the text from your resx files.
Have you considered using $.ajax in combination with ASP.NET WebMethods? It's hard to suggest a more concrete solution to this problem without understanding how your JavaScript/jQuery would consume/process the resources. I assume that they're organized into logical groups (or could be) where you could return several resource strings that belong on a single page.
Assuming that, you could write a very simple C# class -- or use a Dictionary<string, string> -- to return data from your ASP.NET WebMethod. The results would look something like:
[WebMethod]
public Dictionary<string, string> GetPageResources(string currentPage)
{
// ... Organizational stuff goes here.
}
I always separate out my AJAX calls into separate .js files/objects; that would look like:
function GetPageResources (page, callback)
$.ajax({ // Setup the AJAX call to your WebMethod
data: "{ 'currentPage':'" + page + "' }",
url: /Ajax/Resources.asmx/GetPageResources, // Or similar.
success: function (result) { // To be replaced with .done in jQuery 1.8
callback(result.d);
}
});
Then, in the .js executed on the page, you should be able to consume that data like:
// Whatever first executes when you load a page and its JS files
// -- I assume that you aren't using something like $(document).ready(function () {});
GetPageResources(document.location, SetPageResources);
function SetPageResources(resources) {
for (currentResource in resources) {
$("#" + currentResource.Key).html(currentResource.Value);
}
}
I know it's to late but want share my experience in this task)
I use AjaxMin. It can insert resx key values into js file on build event.
It's not common way but it keeps html without unneeded script blocks and can be done during minification process if you have it.
It works like this:
ajaxmin.exe test.js -RES:Strings resource.resx -o test.min.js
Also you need to do the same for ech locale if you have many.
Syntax to write resource keys in js (and also css) is written here:
Js localization
Css localization
How about injecting it as part of a javascript control initialization? what i do is as follows:
I have a self-contained javascript control - call it CRMControl, which has an init method called setupCRMControl, to which i pass a settings object. When i initialize it, i pass an object containing all the resources i need inside javascript as follows:
CRMControl.setupCRMControl({
numOfCRMs: 3,
maxNumOfItems: 10,
// then i pass a resources object with the strings i need inside
Resources: {
Cancel: '#Resources.Cancel',
Done: '#Resources.Done',
Title: '#Resources.Title'
}
});
Then, inside this javascript control:
var crmSettings = {};
this.setupCRMControl(settings) {
crmSettings = settings;
};
and whenever i want to show a resource, i say (for example, show an alert saying 'Done'):
alert(crmSettings.Resources.Done);
You can call it "R" to make it shorter or something, but this is my approach. Maybe this may not work if you have a whole bunch of strings, but for manageable cases, this may work.

Dynamically including javascript files only once

I have a javascript function I'm writing which is being used to include an external JS file, but only once. The reason I need such a function is because it is being called when some content is loaded via AJAX and I need to run page-specific code to that content (no, just using .live won't cover it).
Here's my attempt, shortened for brevity:
$.include_once = function(filename) {
if ($("script[src='" + filename + "']").length === 0) {
var $node = $("<script></script>")
.attr({
src : filename,
type : "text/javascript"
})
;
$(document.body).append($node);
}
};
This works fine: the function is called, it loads the external file, and that file is being run when loaded. Perfect.
The problem is that it will always re-load that external file: the query I'm using to check for the presence of the script always finds nothing!
When debugging this, I added some lines:
alert($("script").length); // alerts: 4
$(document.body).append($node);
alert($("script").length); // alerts: 4
Looking in the dynamic source (the HTML tab of Firebug), I can't find the script tag at all.
I know that I could maintain an array of files that I've previously included, but I was hoping to go with a method such as this, which (if it worked), seems a bit more robust, since not all the JS files are being included in this way.
Can anyone explain the behaviour seen in this second snippet?
jQuery is a bit of a dumb-dumb in this case; it doesn't do at all what you'd expect. When you append($node) jQuery does this:
jQuery.ajax({
url: $node.src,
async: false,
dataType: "script"
})
Woops! For local files (eg on the same domain) jQuery performs a standard XMLHttpRequest for the .js file body, and proceeds to "eval" it by a whole convoluted process of creating a <script> tag (again!) and settings it's contents to your .js file body. This is to simulate eval but in the global context.
For cross-domain files, since it cannot perform the standard XMLHttpRequest due to the same-domain policy, jQuery once again creates a <script> element and inserts it into <head>.
In both the local and cross-domain cases above jQuery finally gets around to doing this:
head.removeChild(script);
And booms your .length check! Bummer.
So on to your problem, don't bother jQuery with this. Just do
document.getElementsByTagName('head')[0]
.appendChild(
document.createElement('script')
)
.src = filename;
Which will do what you'd expect, particularly wrt querying for it later.
You're trying to solve a problem that has already been solved several times over. Try LazyLoad for example. There are also similar plugins for jQuery.
Instead of setting the source attribute of the script-tag, set the "text" attribute of the script tag. This works in all modern browsers (the application where I use that in practice does not support IE6, so I do not know about this creep...).
In practice it would look like this (you HAVE TO add code to omit double inclusion on yourself - e.g. a simple array of all alread loaded scripts, though thats very application specific, and why should you anyway load code twice? try to omit double-loading code...!):
var script_source_code_string = <some dynamically loaded script source code>;
var $n = $("<script></script>");
$n.get(0).text = script_source_code_string;
$(document.body).append($n);
Or even simpler (without jquery, my code at this stage does not know jquery, it may also be loaded dynamically):
var script_source_code_string = <some dynamically loaded script source code>;
var s = document.createElement('script');
document.getElementsByTagName('head')[0].appendChild(s);
s.text = script_source_code_string;

Categories