Overview of jQuery - HTML5 Programming for ASP.NET Developers - page 58

TemperatureData Convert(TemperatureData t);
}
public class Service : IService
{
public TemperatureData Convert(TemperatureData t)
{
if (t.Unit == "C")
{
t.Value = (t.Value * 1.8m) + 32;
t.Unit = "F";
}
else
{
t.Value = (t.Value - 32) / 1.8m;
t.Unit = "C";
}
return t;
}
}
}
The TemperatureData class represents the data contract of the WCF service and contains two data
member properties: Value and Unit . The IService interface represents a service contract for the service
and defines a single method Convert() . The Convert() method accepts a TemperatureData object and
returns a TemperatureData object after converting the temperature value to the other scale.
Notice that Convert() is decorated with an [WebInvoke] attribute. Due to this attribute, Convert()
becomes callable from the client-side jQuery code. The RequestFormat and ResponseFormat properties of
the [WebInvoke] attribute specify JSON as the communication format during request and response,
respectively. The Method property specifies that Convert() can be invoked by HTTP POST requests. The
Service class implements Convert() . The Convert() method checks the Unit of the incoming
TemperatureData object and, depending on the Unit , converts the Value to the other scale.
The Service class's Convert() method can be called using jQuery's $.ajax() function as shown in
Listing 2-16.
Listing 2-16. Using $.ajax() to Call the WCF Service Convert() Method
$(document).ready(function () {
$("#Button1").click(function () {
url = "Service.svc/Convert";
data = '{"Value":"' + $("#Text1").val() + '","Unit":"' + $("#Select1").val() + '"}';
$.ajax({
type: "POST",
url: url,
data: data,
contentType: "application/json; charset=utf-8",
dataType: "json",
success: OnSuccess,
error: OnError
})
});
});