How to declare a local variable in Razor?

Question

I am developing a web application in asp.net mvc 3. I am very new to it. In a view using razor, I'd like to declare some local variables and use it across the entire page. How can this be done?

It seems rather trivial to be able to do the following action:

@bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
@if (isUserConnected)
{ // meaning that the viewing user has not been saved
    <div>
        <div> click to join us </div>
        <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
    </div>
}

But this doesn't work. Is this possible?

Community · Accepted Answer · 2019-04-29 13:07:01Z

638

I think you were pretty close, try this:

@{bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);}
@if (isUserConnected)
{ // meaning that the viewing user has not been saved so continue
    <div>
        <div> click to join us </div>
        <a id="login" href="javascript:void(0);" style="display: inline; ">join here</a>
    </div>
}

edited Apr 29, 2019 at 13:07

CommunityBot

11 silver badge

answered Jul 6, 2011 at 19:18

Tomas Jansson

23.6k18 gold badges92 silver badges147 bronze badges

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

6 Comments

Stefan Paul Noack Over a year ago

How do you do this in VB.NET?

Stefan Paul Noack Over a year ago

oh, i found it out by myself: @Code .. End Code instead of @{ .. }

Tomas Jansson Over a year ago

@Abhijeet.Nagre, in the question he writes: @bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName); but variable definition must be inside a "code block". I can't give a better answer to why then that, it's just how razor works.

Jon Story Over a year ago

@AbhijeetNagre - Razor is usually quite good at understanding where code starts and ends, but it's not perfect. Sometimes we just have to give it a little hint regarding what should be treated as Razor/C#, and what shouldn't. If you ever get a Razor error, adding { } tags is usually the first step

mekb Over a year ago

@StefanPaulNoack I think you can use parentheses ( ) instead of brackets { } for VB.

|

Flimtix · Accepted Answer · 2022-05-26 12:58:23Z

65

I think the variable should be in the same block:

@{
    bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
    if (isUserConnected)
    { 
        // meaning that the viewing user has not been saved
        <div>
            <div> click to join us </div>
            <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
        </div>
    }
}

edited May 26, 2022 at 12:58

Flimtix

4081 gold badge8 silver badges18 bronze badges

answered Feb 9, 2012 at 0:07

Khasha

1,6791 gold badge14 silver badges19 bronze badges

3 Comments

Matthew Walton Over a year ago

That seems to be the case, in MVC3 at least.

SharpC Over a year ago

Excellent! Any idea how you would then use the variable isUserConnected again further down the page?

Dan Mangiarelli Over a year ago

@SharpC Once you declare a variable like that it's available in the rest of that .cshtml file. Later in the file you could do something like @if (isUserConnected) { /* stuff if connected */ } or <div>Connected? @isUserConnected</div> (this works better with strings). It's not available outside that file though (e.g. you'll have to declare it separately in partials).

DBS · Accepted Answer · 2015-03-12 12:37:29Z

18

You can also use:

@if(string.IsNullOrEmpty(Model.CreatorFullName))
{
...your code...
}

No need for a variable in the code

edited Mar 12, 2015 at 12:37

DBS

10.1k4 gold badges40 silver badges61 bronze badges

answered Aug 25, 2013 at 12:13

marcel

3134 silver badges10 bronze badges

1 Comment

Owen Pauling Over a year ago

This doesn't provide an answer to the question.

aloisdg · Accepted Answer · 2017-03-28 08:37:38Z

18

Not a direct answer to OP's problem, but it may help you too. You can declare a local variable next to some html inside a scope without trouble.

@foreach (var item in Model.Stuff)
{
    var file = item.MoreStuff.FirstOrDefault();

    <li><a href="@item.Source">@file.Name</a></li>
}

edited Mar 28, 2017 at 8:37

answered Mar 21, 2017 at 15:56

aloisdg

23.8k7 gold badges93 silver badges114 bronze badges

Comments

Brian · Accepted Answer · 2015-06-12 18:05:39Z

15

If you're looking for a int variable, one that increments as the code loops, you can use something like this:

@{
  int counter = 1;

  foreach (var item in Model.Stuff) {
    ... some code ...
    counter = counter + 1;
  }
}

answered Jun 12, 2015 at 18:05

Brian

3,7232 gold badges25 silver badges34 bronze badges

Comments

mfluehr · Accepted Answer · 2020-12-24 06:09:32Z

4

If you want a variable to be accessible across the entire page, it works well to define it at the top of the file. (You can use either an implicit or explicit type.)

@{
    // implicit type
    var something1 = "something";

    // explicit type
    string something2 = "something";
}

<div>@something1</div> @*display first variable*@
<div>@something2</div> @*display second variable*@

edited Dec 24, 2020 at 6:09

mfluehr

3,2452 gold badges30 silver badges37 bronze badges

answered Nov 21, 2017 at 22:33

d384

511 bronze badge

Comments

sajadre · Accepted Answer · 2020-03-19 07:43:52Z

3

you can put everything in a block and easily write any code that you wish in that block just exactly the below code :

@{
        bool isUserConnected = string.IsNullOrEmpty(Model.CreatorFullName);
        if (isUserConnected)
        { // meaning that the viewing user has not been saved
            <div>
                <div> click to join us </div>
                <a id="login" href="javascript:void(0);" style="display: inline; ">join</a>
            </div>
        }
    }

it helps you to have at first a cleaner code and also you can prevent your page from loading many times different blocks of codes

edited Mar 19, 2020 at 7:43

answered Dec 18, 2019 at 12:15

sajadre

1,1812 gold badges17 silver badges33 bronze badges

Collectives™ on Stack Overflow

How to declare a local variable in Razor?

7 Answers 7

6 Comments

3 Comments

1 Comment

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

7 Answers 7

6 Comments

3 Comments

1 Comment

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related