If my javascript/jquery code is written inside a jsp-file, I can refer to Spring's modelAttribute value with "${varName}".
However I would like to move the javascript code into it's own file to keep the jsp-file more readable. When I do that, it won't however be able to find that modelAttribute anymore. How should I solve this problem?
How can I point to model attribute from a .js -file?
Thanks in advance!
Alright, I've experimented on my end to try to find and answer for this question.
Actually, it seems there's no direct solution, and here's why:
When you are moving your Javascript code to a separate file, this means that the browser will launch a separate request to fetch that file. As such, data that you store in your request scope (a.k.a. ${varName}) is not part of the request that fetches the .js file; it's only part of the request that fetches your .jsp file instead. As such, the ${varName} value will not be available in your Javascript file.
Another reason on top of the above: .js files are not processed as server-side code by the web engine (most likely Tomcat in this case), so the ${varName} text is outright ignored. For fun, I tried to do a hack: I renamed my script file from .js to .jsp, and used this within my .jsp page:
<script type="text/javascript" src="js/actually_javascript.jsp"></script>
It fooled the web server to process the file server-side, but this still didn't work, because of reason #1 stated above. It could work if you stored the value in the session instead, but at the end of the day, it would be kind of an ugly hack and you'd lose out on the code highlighting and completion features of your IDE, which would be fooled into thinking you're editing an actual .jsp file. Not recommended.
To conclude, I think the only way to access {$varName} inside your JavaScript is either:
Having the Javascript being a part of your .jsp file, within <script> tags
Having your Javascript in its own .js file, but still having a <script> tag in your .jsp page which initializes the module you programmed in the .js file and passes the values from the request, like ${varName}
You should initialize your javascript file via your jsp file.
Example:
Create a seperate script section for initialization of your variables after loading the .js file in your jsp page:
<script src="js-path/file.js"></script>
<script>
init(${varFromModel1}, ...);
</script>
And define the init-method in your javascript file:
function init(param1, ...) {
// initialize variables of .js file here
}
Remember, for this to work, you need to ensure, that the model-attribute output has correct javascript syntax.
Related
I am using spring boot to provide data to thymeleaf.
var list = [(${listStudents})];
listStudents is a list of students with the help of which I populate data in HTML which is working fine but fetching the same list in java script using thymeleaf shows error in the above line as:
, expected.
I have added th:inline="javascript" attribute to script tag in HTML file as:
<script th:inline="javascript" src="home_script.js"></script>
Trying to solve this since yesterday.
Thanks in advance!
The , expected error is the standard JavaScript syntax error for var list = [(${listStudents})];. To handle this, Thymeleaf supports placing its inline expressions inside JavaScript comments:
var list = /*[[${listStudents}]]*/ [];
Because the Thymeleaf expression is in a JS comment, note how we have to provide a default (visible) JS value, to keep JavaScript from raising a different syntax error. I used [] because you have a list. You could have used '', or null or whatever is most suitable. Assuming your Thymeleaf is rendered correctly, this extra syntax will be ignored.
See JavaScript natural templates for details.
However, I do not think this will completely resolve your problem, unless you have already configured a JavaScript template resolver in your application.
You are using this:
<script th:inline="javascript" src="home_script.js"></script>
First of all, the th:inline="javascript" portion has no effect, because your JavaScript code is in an external file: home_script.js (i.e. it is not embedded in your HTML file).
If you want Thymeleaf to process the Thymeleaf expressions in that separate JS file, you have to tell Thymeleaf to explicitly process external JavaScript files (just like it processes HTML files).
You probably only have a HTML resolver - and your JS code is not embedded in your HTML file - it is in its own separate JS file. See this demo application which shows how to set up what I think you may need.
Alternatively you can simply embed your JS directly into the <body> of your HTML file, and don't use an external JS file:
<body>
<script th:inline="javascript">
var list = /*[[${listStudents}]]*/ [];
</script>
</body>
If you still need to use an external JS file, you can assign all your Thymeleaf-generated variables inside your HTML file (like the example above) and then pass these variables as function parameters into the various JavaScript functions in your JS file.
Using this approach means your JS file does not need to contain any Thymeleaf expressions - it just receives the rendered values from the JS fragment in your HTML file.
You should use [[${listStudents})]] (so 2 square brackets, not using round brackets)
I'm loading javascript variables in the product.liquid file on shopify.I'm also loading an external javascript file as well. This javascript file is using the variables that i put in the liquid file. Seems like the variables are undefined in the external JS file eventhough i gave them values
When you render Liquid, you can populate JS variables. The thing is, you need to wait for the DOM to be downloaded and for all the rendered code to be delivered to the browser before you try and use it or access it. Ensure you are waiting properly before trying to access your variables.
In a common JS library like jQuery, you can use this block to wrap your code:
document.addEventListener('DOMContentLoaded', function() {
// stuff
});
I have some html, that had a bunch of JS code inside a script tag. So I moved it to a separate .js file.
JS code also loaded some variables from CGI, using strings in a form of <%ejGet(var)%>. But after separating the code from HTML file, the strings don't get replaced with data from the server.
Is there a way to include a JS file as if it was written inside a script tag or is there another way to do this?
<script language="javascript">
<!-- hide
var syncNvram = '<%ejGetWl(wlSyncNvram)%>';
...about 1000 lines more...
</script>
So after moving this code to a separate file, the variables don't load.
The problem is that your <% ejGetWl(wlSyncNvram) %> is being executed on the server by some templating or processing engine before it gets sent to the browser, so the browser is actually seeing the output, e.g.
var syncNvram = 'abcdefg'; // or whatever the output is
The question you are really asking is, can my server side templating/processing engine process a javascript file as opposed to an html file.
The answer is, it depends on the template/processing engine, but in general, this is a bad idea. JS files should remain static assets for lots of good reasons (breaking code, distributing via CDNs, etc.)
The better thing to do is separate them out:
<script>var syncNvram = '<%ejGetWl(wlSyncNvram)%>';</script>
<script src="myfile.js"></script>
Declare it separately.
Even better might be using ajax to get it, but that is a whole different architecture which may not suit here.
To do that you need to generate the script from the CGI program.
<script src="/cgi-bin/example.js.cgi"></script>
Of course, that will be a different CGI program so getting the variables in the right state may be problematic.
Usually you would solve the problem using a different approach: include the data in the document (either in the script element or in an element such as a <meta> element, a hidden input or a data-* attribute on something relevant and then have a static script read the data from the DOM.
I am using Knockoutjs in my asp.net MVC-5 application. I have the following javascript in view:
<script type="text/javascript">
var model = "#Html.Raw(Json.Encode(Model))";
$.get("#Url.Action("_CityPartial")" ...)
//any much more code using similar Html helpers + pure javacsript code.
</script>
Now i want to know, is there any way to transfer this javascript code in a separate js file (keeping Html helpers as it is).
I want to transfer javascript code to separate file because i dont want any user to check my javascript code (using chrome inspect element or any other way).
If the transfer is not possible than please let me know if there is a any way to minifiy the javascript in view itself ??
You could create an external .js file with your code in and pass your serialized json object to it like this:
<script type="text/javascript">
var model = #Html.Raw(Json.Encode(Model));
DoThis(model);
</script>
This has the benefits of keeping the main body of javascript in a separate file.
Any other razor variables can be passed across to the methods defined in the javascript in the same manor as the model has been above.
However as Stanyer mentions this is still javascript and it will run on the client.
You can load it via an external JavaScript file, but unfortunately as JavaScript is a client-side scripting language regardless of whether its loaded inline or externally, the client can still view the code which is being executed on their browser.
You mention minifying - again this can still be interpreted by a client if they really wanted to see your code, but there are many tools online which can minify your JavaScript for you.
Examples:
http://jscompress.com/
http://www.jsmini.com/
No you cant keep the #Html helpers in external javascript file. They are all server side syntax and will be rendered in your HTML page inline.
What maximum you can do is, assign it in a var variable in your page and refer it inside a external page.
Background information :
A tool simulates IE behavior, instead of HTML for browser, it uses a special object which contains html segment<![CDATA[ HTML Here or JS here ]]>. The tool disabled the ajax call; however, the activeX works on that tool. In other words, HTML display in browser = special object display. No server side language (i.e. php) allowed.
Problem :
The object developed for that tool contains everything(html+css+js) in one single file. Then it makes developer difficult to manage changes. Currently, when I develop, I copied the HTML from <![CDATA[ All HTML or JS here ]]>; after I modified it , I copied the html file back to <![CDATA[ HTML Here or JS here ]]>. I want the object is more organized, for example: in the html segment of the object, just put something like <![CDATA[<javascript>require a.html<javascript> ]]> , then the content in a.html will be automatically placed in the object. Can you suggest any solution or any library for this problem?
ps: I didn't use requirejs before, it seems requirejs uses ajax call to include text file, is it possible that requirejs uses local path to include a file?
Thank you.
Partial solution to my problem: I used activeX to read the entire file, and used jQuery to set the file content to some html element. so the js will look like:
<![CDATA[
<script>var k = readfile(getAbsolutePath()+"\\a.html");
jQuery("#display").html(k);<script> ]]>
I think this solution is for my tool only; To make it work, some requirements:
1. can get the absolute path of the text/html file.
2. activeX works.
OK, now that I understood your problem.
Use
<iframe src="another_file.html">
That is probably the only way to load multiple html files without Ajax or PHP, as far as I know.
Per comment from prytsh, using an embed call should do the trick in HTML5:
You can try this by using jquery
//use this line in jquery
$("#id").load("trackingCode.html");