C# variable in .js file from embeded resource in server control ASP.NET

Question

I am building my ASP server control which has some resources. One of them is .js file where i must pass a variable from my ServerControl.cs file.

I know how to for example get resource images in my resource style files and javascript files like this:

var resourceOpen  = "<%=WebResource("PatientList.Images.DirOpen.png")%>" ;
var resourceClose = "<%=WebResource("PatientList.Images.DirClose.png")%>";

background: url('<%=WebResource("PatientList.Images.letter-bg.png")%>');

I want to do the same with my public variables in my server control .cs file Let's say i've got

public string TestVariable = "It works"

How to pass it to javascript file in my resources?

var jsvariable = "<%=TestVariable%>"

Doesn't work. It seems that only WebResource(...) works. When i try to use variables, when I make something like this:

alert("<%=TestVariable%>");

The window with string "<%=TestVariable%>" will appear instead of "It works"

It should work... except for the obvious 'you're missing semicolons'. If you're using VS (as I am) intellisense shows variables. — carny666
– carny666, Commented Jun 22, 2012 at 11:36
It works but not in my embeded resources javascript files. Only when i have separate javascript and c# variable in my codebehind to my aspx file. But i want to make server control .dll file containing everything. There the problem occurs. It's strange because it works with WebResource(...) inside <%= %> but seems to fail with everything else. — Tomasz Sikora
– Tomasz Sikora, Commented Jun 22, 2012 at 11:46
Ahh I see. Maybe you should pass the values to your javascript functions from the main page. — carny666
– carny666, Commented Jun 22, 2012 at 12:11
if find it odd that WebResource works because DateTime.Now.ToString() does not. — carny666
– carny666, Commented Jun 22, 2012 at 12:15

Robba · Accepted Answer · 2012-06-22 14:42:12Z

1

Maybe I'm not understanding your question correctly, but you have a server control that references an external JavaScript file, but in the external file you want to use a property on the control.

If that is what you are asking, then I'm afraid that it's not possible without writing custom handlers or something of the sort. You see, the external JavaScript file is requested by the client seperately from your control execution. At the time the JavaScript file is served by the server, the control has long been destroyed.

Here's what happens:

A request comes to your server for the page
The page loads and creates your usercontrol and a LINK to an external javascript file
The client gets the result from the server
The client sees a link to the external javascript file and requests it from the server
The request for the javascript file comes in on the server
The server gives the client the javascript file

As you can see, there are two requests coming in (step 1 and step 5). In the second request, the one for the javascript file, you no longer have the control with the property available (which was in step 1).

The only way I can think of to get this done is to do something with a custom handler to provide the javascript. This way you can pass any variables as querystring values and have the custom handler insert them into your java script.

I hope this answers your question.

answered Jun 22, 2012 at 14:42

Robba

8,46413 gold badges52 silver badges80 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Tomasz Sikora Over a year ago

Thank you for your answer. But i have javascript file as an embeded resource in my server control and i CAN parse this file when i want to get other resources from my control like images (as presented in my question) I only had to add PerformSubstitution = true to my AssemblyInfo.cs file. So when I can PARSE .js file before it loads i don't believe there is no option to get single variables from c# code. But i know only how to get resources... variables don't work :(

Robba Over a year ago

You can add external images because they are constants. From your original post you are able to reference "PatientList.Images.letter-bg.png" because this file is hard compiled into your assembly and as such is always there. The value of your local variable "TestVariable" is only available in the specific request that fills it. The follow up request that actually gets the JavaScript file content no longer has that variable.

Collectives™ on Stack Overflow

C# variable in .js file from embeded resource in server control ASP.NET

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related