ASP.NET MVC - Pass array object as a route value within Html.ActionLink(...)

Question

I have a method that returns an array (string[]) and I'm trying to pass this array of strings into an Action Link so that it will create a query string similar to:

/Controller/Action?str=val1&str=val2&str=val3...etc

But when I pass new { str = GetStringArray() } I get the following url:

/Controller/Action?str=System.String%5B%5D

So basically it's taking my string[] and running .ToString() on it to get the value.

Any ideas? Thanks!

Answer 1

I'd use POST for an array. Aside from being ugly and an abuse of GET, you risk running out of URL space (believe it or not).

Assuming a 2000 byte limit. The query string overhead (&str=) reduces you to ~300 bytes of actual data (assuming the rest of the url is 0 bytes).

Answer 2

Try creating a RouteValueDictionary holding your values. You'll have to give each entry a different key.

<%  var rv = new RouteValueDictionary();
    var strings = GetStringArray();
    for (int i = 0; i < strings.Length; ++i)
    {
        rv["str[" + i + "]"] = strings[i];
    }
 %>

<%= Html.ActionLink( "Link", "Action", "Controller", rv, null ) %>

will give you a link like

<a href='/Controller/Action?str=val0&str=val1&...'>Link</a>

EDIT: MVC2 changed the ValueProvider interface to make my original answer obsolete. You should use a model with an array of strings as a property.

public class Model
{
    public string Str[] { get; set; }
}

Then the model binder will populate your model with the values that you pass in the URL.

public ActionResult Action( Model model )
{
    var str0 = model.Str[0];
}