i have create one web services.
 that service in one parameter is class.
how to pass postman parameter in class object. 
 
it's my code. 
[WebMethod]
        [ScriptMethod(ResponseFormat = ResponseFormat.Json)]
        public List<strudent> SaveOrder(strudent stud)
        {
            var list=new List<strudent>();
            list.Add(stud);
            return list;
        }
 
 
//Class  
 public class strudent
    {
        public string Fname { get; set; }
        public string Lname { get; set; }
        public string data { get; set; }
    }