How can I call a web service and pass parameters using the URL

Question

How can I call a ASP .NET web service and pass parameters using the URL?

For example, the URL for the service is like,

http://[localhost]:31856/MySystem/MyAPI.asmx?op=getHeight

I need to pass two parameters a and b, I tried

http://[localhost]:31856/MySystem/MyAPI.asmx?op=getHeight?a=254&b=1

But failed.

Please advice.

Many Thanks,

Answer 1

If you need to pass more than one parameter, use this format param1=value1&param2=value2 and so on.So your link should be:

http://[localhost]:31856/MySystem/MyAPI.asmx/AnyMethodName?op=getHeight&a=254&b=1

You need a method like this.This method returns a list of strings,its just for demonstration.

    [WebMethod]
    public List<string> AnyMethodName(string op, string a, string b)
    {
       //Do whatever you want, get answer
        return (ans.ToList());
    }

Answer 2

I had the same problem and I needed to add the following in my webconfig inside the system.web -tag:

<webServices>
<protocols>
<add name="HttpGet" />
</protocols>
</webServices>

The rest was pretty much like already mentioned (using the example from Ashwin's answer, just removed the op-parameter)

   [WebMethod]
    public List<string> AnyMethodName(string a, string b)
    {
       //Do whatever you want, get answer
        return (ans.ToList());
    }

After that I was able to call the webservice with the following (removed the op-parameter again):

http://localhost/MySystem/MyAPI.asmx/AnyMethodName?a=254&b=1