Using variables in C# tags in html, using asp.net

Question

I was wondering if it was possible to define and use a variable in your html using C# tags.

So for instance

<% String var = "simpleString"; %>
<link rel="stylesheet" type="text/css" href="style.css?v=<%Response.Write(var);%>" />

I have been trying to get something like this to work. When I write it like

<% String var = "pineapples"; Response.Write(var);%>

it works, but when I write them in separate tags it doesn't seem to read it as a variable.

It might be worth being clear on what it does do in that situation (ie say if it throws an error, displays that text literally, etc.). Sadly I've not done webforms for ages since I am more a razor man now so not sure how much help I can be. I do have a vague recollection though of always replacing the whole attribute value rather than just part of the it but not sure if that is a genuine useful memory or not. :) — Chris
– Chris, Commented Jul 17, 2015 at 9:02

marc_s · Accepted Answer · 2015-07-17 09:12:00Z

3

var is a keyword in c# used to implicitly type a variable.

String is explicitly typed.

You have used both in your example:

String var = "simpleString";

You could change it to:

String var1 = "simpleString";

using your desired variable name above.

<% String var1 = "simpleString"; %>
<link rel="stylesheet" type="text/css" href="style.css?v=<%=var1%>" />

Also note that from mark-up you can use <%= %> to output rather than Response.Write.

edited Jul 17, 2015 at 9:12

marc_s

760k186 gold badges1.4k silver badges1.5k bronze badges

answered Jul 17, 2015 at 9:05

hutchonoid

33.4k15 gold badges102 silver badges106 bronze badges

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

5 Comments

Wim Over a year ago

hi you wouldnt happen to know who to escape that. so <div> <%=var1%> outputs fine, but when its like href="style.css?v=<%=var1%>" it outputs href="style.css?v=<%=var1%>" instead of href="style.css?v=simpleString>". i know its because it sees it as string and not a variable, but how would i make it see it as a variable?

hutchonoid Over a year ago

@Wim If I understand you correctly, try changing it to single quotes i.e. <link rel='stylesheet' type='text/css' href='style.css?v=<%=var1%>' />

Wim Over a year ago

see the problem is that inserting <%var1%> inside quotes is the problem. so when i make the variable, VS highlights it and says its unused. when i type the variable inside quotes it would not recognize it as a variable at all so in other words the statement that you gave me href='style.css?v=<%=var1%>' outputs the same as before. it outputs the var1 as a string instead of the value inside it

hutchonoid Over a year ago

@Wim That is odd, I don't get that. Is it razor that you are using and not an .aspx?

Wim Over a year ago

im pretty sure. its a aspx file that i am editing, does that make a difference?

Collectives™ on Stack Overflow

Using variables in C# tags in html, using asp.net

1 Answer 1

5 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

5 Comments

Your Answer

Sign up or log in

Post as a guest

Related