how to call a variable in code behind to aspx page

Question

i know i have seen this but cant recall the correct way of doing it... basically i have a string variable called "string clients" in my .cs file.. but i wasn't to be able to pass it to my aspx page something like

<%=clients%>

please correct me, i do not recall or not sure how to do this. (new to c#) and when i googled it.. it was not clear.. or not many of these out there.. searched as

"asp.net c# <%= %> not consistent results.. maybe because i do not know how to call these..

possible duplicate of [get property from code behind into aspx page](http://stackoverflow.com/questions/1924309/get-property-from-code-behind-into-aspx-page) — onof, Sep 13 '11 at 19:52

Joel A. Villarreal Bertoldi · Accepted Answer · 2011-09-13T19:03:26.030

66

The field must be declared public for proper visibility from the ASPX markup. In any case, you could declare a property:


private string clients;
public string Clients { get { return clients; } }

UPDATE: It can also be declared as protected, as stated in the comments below.

Then, to call it on the ASPX side:

<%=Clients%>

Note that this won't work if you place it on a server tag attribute. For example:

<asp:Label runat="server" Text="<%=Clients%>" />

This isn't valid. This is:

<div><%=Clients%></div>

edited Sep 13 '11 at 19:03

answered Sep 13 '11 at 18:55

Joel A. Villarreal Bertoldi

7,829
8
35
51

2

and how do i call it in .aspx page? – user710502 Sep 13 '11 at 18:57
Added some example and some explanation. – Joel A. Villarreal Bertoldi Sep 13 '11 at 18:59
3

if you replace the double quotes to single, it will work. – Mike May 09 '17 at 19:30

score 30 · Answer 2 · answered Sep 13 '11 at 19:02

In your code behind file, have a public variable

public partial class _Default : System.Web.UI.Page
{
    public string clients;

    protected void Page_Load(object sender, EventArgs e)
    {
        // your code that at one points sets the variable
        this.clients = "abc";
    }
}

now in your design code, just assign that to something, like:

<div>
    <p><%= clients %></p>
</div>

or even a javascript variable

<script type="text/javascript">

    var clients = '<%= clients %>';

</script>

Maxim V. Pavlov · Answer 3 · 2011-09-13T19:06:13.567

9

For

<%=clients%>

to work you need to have a public or protected variable clients in the code-behind.

Here is an article that explains it: http://msdn.microsoft.com/en-us/library/6c3yckfw.aspx

edited Sep 13 '11 at 19:06

answered Sep 13 '11 at 18:56

Maxim V. Pavlov

10,303
17
74
174

1

protected works just as well since the aspx markup is inheriting the code behind. – gislikonrad Sep 13 '11 at 19:00

score 7 · Answer 4 · answered Sep 13 '11 at 19:01

7

Make sure that you have compiled your *.cs file before browsing the ASPX page.

answered Sep 13 '11 at 19:01

Mark Cidade

98,437
31
224
236

This was my issue. One has to build the project before calling it from ASPX, otherwise you will get intellisense marking it as non existent. – Ghasan غسان Oct 27 '17 at 03:23

score 6 · Answer 5 · answered Sep 13 '11 at 18:59

6

First you have to make sure the access level of the variable is protected or public. If the variable or property is private the page won't have access to it.

Code Behind

protected String Clients { get; set; }

Aspx

<span><%=Clients %> </span>

answered Sep 13 '11 at 18:59

Cris Valenzuela

372
3
9

Tchami · Answer 6 · 2011-09-13T19:00:40.127

You need to declare your clients variable as public, e.g.

public string clients;

but you should probably do it as a Property, e.g.

private string clients;
public string Clients{ get{ return clients; } set {clients = value;} }

And then you can call it in your .aspx page like this:

<%=Clients%>

Variables in C# are private by default. Read more on access modifiers in C# on MSDN and properties in C# on MSDN

score 3 · Answer 7 · answered Nov 08 '17 at 22:02

You can access a public/protected property using the data binding expression <%# myproperty %> as given below:

    <asp:Label ID="Label1" runat="server" Text="<%#CodeBehindVarPublic %>"></asp:Label>

you should call DataBind method, otherwise it can't be evaluated.

    public partial class WebForm1 : System.Web.UI.Page
    {
     public string CodeBehindVarPublic { get; set; }
      protected void Page_Load(object sender, EventArgs e)
        {
          CodeBehindVarPublic ="xyz";
       //you should call the next line  in case of using <%#CodeBehindVarPublic %>

          DataBind();
        }

}

score 2 · Answer 8 · answered Sep 13 '11 at 19:01

2

I would create a property to access the variable, like this:

protected string Test
{
    get; set;
}

And in your markup:

<%= this.Test %>

answered Sep 13 '11 at 19:01

James Johnson

45,496
8
73
110

score 1 · Answer 9 · answered Sep 28 '15 at 05:28

The HelloFromCsharp.aspx look like this

 <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="HelloFromCsharp.aspx.cs" Inherits="Test.HelloFromCsharp" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <p>
       <%= clients%>
    </p>
    </form>
</body>
</html>

And the HelloFromCsharp.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Test
{
    public partial class HelloFromCsharp : System.Web.UI.Page
    {
        public string clients;
        protected void Page_Load(object sender, EventArgs e)
        {
            clients = "Hello From C#";
        }
    }
}

how to call a variable in code behind to aspx page

9 Answers9

Linked

Related