In this article I will show you a way to consume a JSON WCF REST Service in Windows Phone 7. This article is divided into four parts.
- Creating a simple WCF REST Service for ADD
- Consuming the JSON REST Service in Windows
Phone 7 application.
- Creating a complex WCF REST Service with
custom classes and types.
- Consuming the complex JSON REST Service in
Windows Phone 7 application.
Creating a simple Add Service
To start with, let us create a WCF REST Service returning JSON as below. There is
one operation contact named Add in the service and that is taking two strings as
input parameters and returning an integer.
[ServiceContract]
public interface
IService2
{
[OperationContract]
[WebGet(UriTemplate="/Add/{Number1}/{Number2}",RequestFormat=WebMessageFormat.Json,
ResponseFormat =
WebMessageFormat.Json
)]
int Add(string
Number1, string Number2);
}
The service is implemented as below:
using
System;
namespace
MultipleBindingWCF
{
public class
Service1 : IService2
{
public int Add(string
Number1, string Number2)
{
int num1 =
Convert.ToInt32(Number1);
int num2 =
Convert.ToInt32(Number2);
return num1 + num2;
}
}
Next in this section we need to configure the service. We need to configure the service
webHttpBinding to eanble it as REST Service. So in Web.Config we need to do the
following changes.
<?xml
version="1.0"?>
<configuration>
<system.web>
<compilation
debug="true"
targetFramework="4.0"
/>
</system.web>
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior
name
="servicebehavior">
<serviceMetadata
httpGetEnabled="true"/>
<serviceDebug
includeExceptionDetailInFaults="false"/>
</behavior>
</serviceBehaviors>
<endpointBehaviors>
<behavior
name="restbehavior">
<webHttp/>
</behavior>
</endpointBehaviors>
</behaviors>
<services>
<endpoint
name
="RESTEndPoint"
contract
="MultipleBindingWCF.IService2"
binding
="webHttpBinding"
address
="rest"
behaviorConfiguration
="restbehavior"/>
</service>
</services>
</system.serviceModel>
<system.webServer>
<modules
runAllManagedModulesForAllRequests="true"/>
</system.webServer>
</configuration>
After configuring, the service ready for hosting. You are free to host it either on
Azure, IIS, or Cassini. For local ASP.Net Server hosting press F5. Do a testing
of service in browser and if you are getting expected output, you are good to
consume it in the Windows Phone 7 application.
Consuming the Service in Windows Phone 7
To consume the REST Service in Windows Phone 7 and then parse JSON, you need to add the following references in Windows Phone 7 project.
![WCFWinPhn1.jpg]()
As the design of the page I have put two textboxes and one button. The user will input
numbers to be added in the textbox and on click event of button result would get
displayed in message box. Essentially on click event of the button we will make
a call to the service. The design of the page is as below:
<Grid
x:Name="LayoutRoot"
Background="Transparent">
<Grid.RowDefinitions>
<RowDefinition
Height="Auto"/>
<RowDefinition
Height="*"/>
</Grid.RowDefinitions>
<!--TitlePanel
contains the name of the application and page title-->
<StackPanel
x:Name="TitlePanel"
Grid.Row="0"
Margin="12,17,0,28">
<TextBlock
x:Name="ApplicationTitle"
Text="calling
JSON REST"
Style="{StaticResource
PhoneTextNormalStyle}"/>
<TextBlock
x:Name="PageTitle"
Text="JSON
REST"
Margin="9,-7,0,0"
Style="{StaticResource
PhoneTextTitle1Style}"/>
</StackPanel>
<!--ContentPanel
- place additional content here-->
<Grid
x:Name="ContentPanel"
Grid.Row="1"
Margin="12,0,12,0">
<TextBox
x:Name="txtNumber1"
Height="100"
Margin="-6,158,6,349"
/>
<TextBox
x:Name="txtNumber2"
Height="100"
Margin="-6,28,6,479"
/>
<Button
x:Name="btnAdd"
Height="100"
Content="Add"
Click="btnAdd_Click"/>
</Grid>
</Grid>
On click event of the button we need to make a call to the service as below:
![WCFWinPhn2.jpg]()
And the ServiceURi is constructed as below:
![WCFWinPhn3.jpg]()
There is nothing very fancy about the preceding service call. We are just downloading
JSON as a string using WebClient. However parsing of JSON is the main focus of this
article. To parse we need to write the following code in the completed event.
![WCFWinPhn4.jpg]()
In the preceding code:
-
Converting downloaded string as Stream
-
Creating instance of
DataContractJsonSerializer. In that we are passing type as string since
returned type of service is string.
-
Reading stream into instance of
DataContractJsonSerializer
-
Displaying the result.
Putting all code together you should have following
code to make a call and parse JSON in Windows Phone 7:
using
System;
using System.Net;
using
System.Windows;
using
Microsoft.Phone.Controls;
using
System.Runtime.Serialization.Json;
using System.IO;
using
System.Text;
namespace
ConsumingJSON
{
public partial
class MainPage
: PhoneApplicationPage
{
// Constructor
public MainPage()
{
InitializeComponent();
}
private void
btnAdd_Click(object sender,
RoutedEventArgs e)
{
string Number1 = txtNumber1.Text;
string Number2 = txtNumber2.Text;
string ServiceUri =
"http://localhost:30576/Service1.svc/Rest/add/"
+ Number1 + "/"
+ Number2;
WebClient proxy =
new WebClient();
proxy.DownloadStringCompleted +=
new
DownloadStringCompletedEventHandler(proxy_DownloadStringCompleted);
proxy.DownloadStringAsync(new
Uri(ServiceUri));
}
void proxy_DownloadStringCompleted(object
sender, DownloadStringCompletedEventArgs e)
{
Stream stream =
new MemoryStream(Encoding.Unicode.GetBytes(e.Result));
DataContractJsonSerializer obj =
new
DataContractJsonSerializer(typeof(string));
string result =
obj.ReadObject(stream).ToString();
MessageBox.Show(result);
}
}
}
Creating a complex Service with custom classes and types
Go back to the service and add a custom class as below:
[DataContract]
public class
Student
{
[DataMember]
public string
Name { get; set;
}
[DataMember]
public string
RollNumber { get; set;
}
[DataMember]
public string
Grade { get; set;
}
}
And add one more function to the service. This operation contract will return a List
of Students.
[OperationContract]
[WebGet(UriTemplate =
"/GetStudents", RequestFormat =
WebMessageFormat.Json,
ResponseFormat =
WebMessageFormat.Json
)]
List<Student>
GetStudents();
Next you need to implement the service as below:
public List<Student>
GetStudents()
{
List<Student>
lstStudent = new
List<Student>
{
new
Student { Name = "John " ,RollNumber =
"1" , Grade = "A"},
new
Student { Name = "Dan " ,RollNumber =
"2" , Grade = "Q"},
new
Student { Name = "Pinal " ,RollNumber
= "3" , Grade =
"M"},
new
Student { Name = "Mahesh " ,RollNumber
= "4" , Grade =
"Z"},
new
Student { Name = "Julie" ,RollNumber =
"5" , Grade = "L"},
};
return lstStudent;
}
Configuration will be the same as of simple REST Service returning JSON. Press
F5 to host and test the service.
Consuming complex JSON REST Service in Windows Phone 7 application
At the Windows Phone 7 application, you need to create an entity class. This class
will be representing the Student class of service. Add the Student class to the project as
below:
public
class Student
{
public string
Name { get; set;
}
public string
RollNumber { get; set;
}
public string
Grade { get; set;
}
}
The design page is as below. I have used a button and upon the click event of the button, the
service will be called and the returned data will be bound to the listbox.
<Grid
x:Name="ContentPanel"
Grid.Row="1"
Margin="12,0,12,0">
<Grid.RowDefinitions>
<RowDefinition
Height="*"
/>
<RowDefinition
Height="110"
/>
</Grid.RowDefinitions>
<ListBox
x:Name="lstStudents"
Height="auto"
Width="auto"
>
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel
Orientation="Vertical">
<TextBlock
Text="{Binding
Name}"
Style="{StaticResource
PhoneTextTitle2Style}"
/>
<TextBlock
Text="{Binding
RollNumber}"
Style="{StaticResource
PhoneTextTitle3Style}"
/>
<TextBlock
Text="{Binding
Grade}"
Style="{StaticResource
PhoneTextAccentStyle}"
/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
<Button
Grid.Row="1"
x:Name="btnAdd"
Height="100"
Content="Add"
Click="btnAdd_Click"/>
</Grid>
In the code behind on click event of the button we need to make call using
WebClient again
private
void btnAdd_Click(object
sender, RoutedEventArgs e)
{
WebClient proxy =
new WebClient();
proxy.DownloadStringCompleted += new
DownloadStringCompletedEventHandler(proxy_DownloadStringCompleted);
proxy.DownloadStringAsync(new
Uri("http://localhost:30576/Service1.svc/rest/getstudents"));
}
And need to parse the returned JSON as below. In parameter to create instance of
DataContractJsonSrrializer we are passing List of Student.
void
proxy_DownloadStringCompleted(object sender,
DownloadStringCompletedEventArgs e)
{
Stream stream =
new MemoryStream(Encoding.Unicode.GetBytes(e.Result));
DataContractJsonSerializer obj =
new
DataContractJsonSerializer(typeof(List<Student>));
List<Student>
result = obj.ReadObject(stream) as
List<Student>;
lstStudents.ItemsSource = result;
}
On running you should be getting output as below.
![WCFWinPhn5.jpg]()