Please Follow Below Steps.
1. Add using statement for referencing namespace in the class where you want to add this referenced proxy class.
e.g using myservice1.XYZ;(this is usually a Name which u had provided at the time of adding wcf service)
2. Now you can access the your ServiceClient by doing like this
Myservice1.ServiceClient1 objClient=new MyService1.ServiceClient1();
objClient.YourMethodName(); // here u will get your require method.
Refer below url :
A beginner’s guide for consuming a WCF service in JavaScript using ASP.NET AJAX[
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