Razor/JavaScript and trailing semicolon

Question

Using Visual Studio 2012, on a Razor view page, in the JavaScript section, I am getting what I think is a battle between Razor syntax vs JavaScript syntax. In particular, the trailing semicolon in the script section is flagged by intellisense and a compiler warning (not error) is delivered:

'Warning 13 Syntax error'.

If I remove it, then I get a statement termination recommendation (ReSharper in this case, but just good practice).

<script type="text/javascript">
    $().ready(function(){
        var customer = @Html.Raw(ViewBag.CustomerJSON);  // <- Razor (I think) doesn't like this semicolon
    });
</script>

Is this a bug in Razor? If so, is there a way I can rewrite this to avoid this issue?

Thing

If you are really anal about it.. like some people 'hint' .. you can do something like @Html.Raw(ViewBag.CustomerJSON) + ''; Because the JavaScript validator is expecting integer or text. It does absolutely nothing to the result but removes the red squiggle. Warning: Overusing this might burn your eyes later on. – Matinee

Another hackish workaround: var data = [@Json.Encode(someObject)][0]; that works for c# calls that are returning JSON objects, not strings or numbers. – Enfranchise

I wouldn't advise creating arrays for every javascript value simply to alleviate an IDE issue. – Litigable

Answer 1

Is this a bug in Razor?

Absolutely not. Run your application, and it will work as expected.

It is a bug in the tools you are using (Visual Studio 2012, ReSharper, ...) that are incapable of recognizing perfectly valid syntax and warning you about something that you shouldn't be warned about. You could try opening an issue on the Microsoft Connect site and signalling this bug if that hasn't already been done.

Barytes

Looks like there is a connect bug for it here: connect.microsoft.com/VisualStudio/feedback/details/777108/… – Tidewaiter

There is another more active connect bug for it at connect.microsoft.com/VisualStudio/feedback/details/760339/… - doesn't look like Microsoft are going to fix this one in 2012 though – Locality

super-annoying not fixed in VS 2013, either, I just upvoted the connect bug, suggest others do the same. – Ecology

Still an active bug in VS 2013 Update 2. It also manifests after a comma. EX: { prop: @Model.Prop, <== THIS COMMA DOES IT TOO! } – Bowerbird

Also an issue when passing a Razor object as a param into a javascript object: foo.bar('something', @JavaScriptConverter.Serialize(pizza)); – Testicle

Answer 2

Since this still seems to be happening and it is a nuisance I figured I will at least let others know what I ended up using as a "hack". I don't want to ignore the warning and would rather accept a hokier syntax (and yes someone is going to say this will kill performance :))

What I use as a workaround is to use a client side addition at the end. For me this error occurred on defining an "integer" constant, so

window.foo = @(Model.Something);

gave me the good old semicolon error. I simply changed this to:

window.foo = @Model.Something + 0;

(In the stated questions case you should just be able to add '', so + ''.

I know there is a whole another addition happening on the client and it isn't elegant, but it does avoid the error. So use it or don't, but I prefer this over seeing the warning/error.

If someone knows of a server-side syntactical workaround for this I would prefer this to the client-side one, so please add.

Spill

for the general case, you may simply do: window.foo = [@Model.Something][0] – Pinta

I adapted this answer for strings; @Html.Raw(Json.Encode(Model.Where(m => m.Apply)))+"" , – Schnauzer

@andrewjs You recommend creating an array just to get around these IDE errors? Not a good practice at all. – Litigable

This does not work for objects. + 0 works for numbers and + '' works for strings. If you use an encoded JSON, you'll get a string like this [object Object]0 which is wrong. The identity function idea and the array workaround in the other answers work very well for all data types. – Gruff

Answer 3

I found that wrapping the Razor syntax in a JavaScript identity function also makes the IDE happy.

<script type="text/javascript">
    @* I stands for Identity *@
    function I(obj) { return obj; }
    $().ready(function(){
        var customer = I(@Html.Raw(ViewBag.CustomerJSON));
    });
</script>

Fiddling

This is basically what we went with internally as well. We named the function Razor(obj) though. – Litigable

@Litigable I created a Razor function as you did, but then, why can't you just put parens around the value? var i = (@ViewBag.value); ? – Raucous

@Nate That may work. I upgraded to VS2013, where the issue is fixed anyways, so I can't test it anymore. – Litigable

Answer 4

This worked for me:

var customer = @Html.Raw(ViewBag.CustomerJSON + ";")

Roseannaroseanne

This works unless you have two var declarations in a row. Then Razor freaks out on the second one. – Corson

Answer 5

Here's a workaround for booleans:

var myBool = @(Model.MyBool ? "true;" : "false;")

Thayer

Answer 6

This worked for me

@Html.Raw(string.Format("var customer = {0};", ViewBag.CustomerJSON));

Linderman

Answer 7

<script type="text/javascript">
    $().ready(function(){
        var customerName = ('@ViewBag.CustomerName');  // <- wrap in parens
    });
</script>

Isn't it as simple as wrapping in parentheses? Putting values through the console seem to work fine with no side effect.

It works for strings, but it still gives the error for non-quoted values, but I still like this for string values. For numbers you could just use parseInt('@Model.TotalResultCount', 10).

Raucous

For non-strings you can put parentheses around the razor call. Eg: const i = (@((int)Enum.SomeValue)) – Isomeric