MVC - Handling unterminated string literal for new line

Question

In my MVC view am having the below piece of code

<script type="text/javascript">
@foreach (var item in Model.Test)
{
<text> jsFunction(@item.someValue);  </text>
}
</script>

Where am calling the Javascript function based on the data i get from model dynamically.

For Example At run time it is rendered like below based on the model data

jsFunction("Works Fine");  
jsFunction("works Fine"); 

Which correctly calls my javascript function

But in case of a new line getting "unterminated string literal" because of the new line

jsFunction("not working
with new line"); 

What is the best way to handle this Scenario

Thanks

Answer 1

What is the best way to handle this Scenario

Use a JSON serializer which will ensure that the value passed to your javascript function is properly escaped:

<script type="text/javascript">
@foreach (var item in Model.Test)
{
    <text>jsFunction(@Html.Raw(Json.Encode(item.someValue)));</text>
}
</script>

or if you update your jsFunction to take an array instead of a single item you could do this:

<script type="text/javascript">
    var values = @Html.Raw(Json.Encode(Model.Test));
    jsFunction(values);
</script>

and then loop through the normal javascript array that will be passed to your function.

P.S: Don't worry if Razor Intellisense is putting a red squiggle around this code. Visual Studio Intellisense in Razor views doesn't work well. Just ignore the warning and run your application and observe the properly generated code.

Answer 2

Simplest solution is to create a helper or something:

@* declared at top of razor page *@
@helper jsFunction(String str)
{
    str = (str ?? String.Empty).Trim().Replace(Environment.NewLine, "\\n");
    @:jsFunction("@Html.Raw(str)");
}

@* example usage *@
foreach (var item in Model.Test)
{
    @jsFunction(@item.Comment)
}

That would perform sanitization on the string to make it convert \n in to the JavaScript counter-part \\n. You may also include exceptions for quotation marks (turn " into \", etc.)

The better alternative is to use something like JSON.NET though:

<text>jsFunction(@Html.Raw(JsonConvert.Serialize(@item.Comment)))</text>

That would make it completely safe to JavaScript (and handle the exceptions for you).

Answer 3

try this

jsFunction(@Html.Raw(Json.Encode(item.Comment)))

I think this should solve your issue.