Question

I would like to pass some parameters to a web method as an array. The web method’s signature does not have the params keyword.

I have a variable number of parameters (as the web method accepts) so I cannot put the array into n single variables.

How can this be done?

Answer 1

params is just syntactic sugar, why not just do something like this:

var myWebService = new MyWebService();
myWebService.MyMethod(new string[] { "one", "two", "three" });

The method signature on the web service side would just be:

public void MyMethod(string[] values);

If you post your web method maybe I can provide a better answer.

EDIT
If you can’t modify the web method signature, then I would use an extension method to wrap the difficult to call web service. For example, if our web service proxy class looks like:

public class MyWebService
{
    public bool MyMethod(string a1, string a2, string a3, string a4, string a5,
        string a6, string a7, string a8, string a9, string a10)
    {
        //Do something
        return false;
    }
}

Then you could create an extension method that accepts the string array as params and makes the call to MyWebService.

public static class MyExtensionMethods
{
    public static bool MyMethod(this MyWebService svc, params string[] a)
    {
        //The code below assumes you can pass in null if the parameter
        //is not specified. If you have to pass in string.Empty or something
        //similar then initialize all elements in the p array before doing
        //the CopyTo
        if(a.Length > 10) 
            throw new ArgumentException("Cannot pass more than 10 parameters.");

        var p = new string[10];
        a.CopyTo(p, 0);
        return svc.MyMethod(p[0], p[1], p[2], p[3], p[4], p[5], 
                            p[6], p[7], p[8], p[9]);
    }
}

You could then call your web service using the extension method you created (just be sure to add a using statment for the namespace where you declared you extension method):

var svc = new MyWebService();
svc.MyMethod("this", "is", "a", "test");