Converting a C# string array into a Javascript array

Question

I am passing a C# string array into a method that is using TagBuilder to build some Javascript. I don't seem to be able to get at the actual items within the array in my Javascript :

public static IHtmlString NewsTicker(this HtmlHelper htmlHelper, string[] arrTickerContents)
    {
        TagBuilder script = new TagBuilder("script");
        script.Attributes.Add("type", "text/javascript");

        script.InnerHtml = @"

            var rss_scr_contents = new Array();

            $.each('" + arrTickerContents + @"', function (i, objValue) {
                rss_scr_contents[i] = objValue;
        });

        return MvcHtmlString.Create(script.ToString());
    }

This results in the following source code :

var rss_scr_contents = new Array();

            $.each('System.String[]', function (i, objValue) {
                rss_scr_contents[i] = objValue;
        });

What is the correct syntax to do this?

Answer 1

The problem is that arrTickerCountents.ToString() does not return the expected results.

For example, (new [] {"hello", "world"}).ToString() evaluates to "System.String[]", which is not useful here.

A valid way to handle this is to use a convert than can emit a valid JavaScript value from a suitable .NET object - the most common tool is likely a JSON converter. I like Json.NET, but this should work with other converters.

var jsonArray = JsonConvert.SerializeObject(arrTickerContents);
script.InnerHtml = @"
        var rss_scr_contents = [];
        $.each(" + jsonArray + @", function (i, objValue) {
            rss_scr_contents[i] = objValue;
        })
"; // Please make sure to post valid code

Since the above loop does no processing as it stands, consider the simpler alternative. (I prefer to not use var with global window properties.)

script.InnerHtml = @"rss_scr_contents = " + jsonArray + ";";

I recommend JSON for its simpleness and available automatic conversions, although it may not always be applicable. Manually building a JavaScript value (i.e. without a JSON library) should be done with care as it is rather easy to introduce invalid, malicious, or otherwise unexpected output.

Answer 2

I did it in Razor like this with NewtonSoft.

var jsonArray=Newtonsoft.Json.JsonConvert.SerializeObject(arrTickerContents);
var rss_scr_contents = @Html.Raw(jsonArray);

Answer 3

$.each('[' + string.Join(',', arrTickerContents), + ']', function (i, objValue) {