Using .resx Strings in Javascript

If you output a string in ASP.Net MVC using @ (Razor) or <%: %> (aspx), the string will automatically get HTML-encoded.

So if you reference a resource string (.resx) in Javascript,

<script type="text/javascript">
var x = "@resx.StringId";
</script>

AND the string contains characters the HTML-encoded (such as “&” => “&amp;”, umlauts, accented characters, etc.), you’ll end up with a lot of ampersands.

The way I solved this problem in a recent project was to define an HtmlHelper extension like this:

public static IHtmlString JsString<TModel>(this HtmlHelper<TModel> html, string s)
{
  return html.Raw(HttpUtility.JavaScriptStringEncode(s));
}

The string is first Javascript-encoded, and then written to the response stream unchanged using HtmlHelper.Raw().