how to pass function name in url while using some web service in objective c?

I am a beginner in i phone development.I am,right now, using web service to fetch data on my page.now the thing is that i have 2 functions in the same webpage. now i want to fetch data from only 1 function at the time when my url is passed. so how can i pass the argument? note that,my main purpose is to convert data into json format.my URL that i run in web browser is like :

http://localhost/abc/webservices/mainPage.asmx?op=GetEmpDetail

how can i change its format,so that i can开发者_如何学JAVA use it in objective c?my function name is getEmpDetail.

Thank you in advance.

Not Sure but try this out.

nsurl *url =http://localhost/abc/webservices/whatever/GetEmpDetail?Param1=value1&Param2=value2

url = [url stringByAddingPercentEscapesUsingEncoding:NSASCIIStringEncoding];