InitParams in Silverlight

Introduction

If you are developing a Silverlight Application, and you need to pass some parameters inside – for example a key and value pair then we can pass the key value pair from the aspx page itself. We will see how we can do this in Silverlight.

Create a Silverlight Project



Figure 1.1 Creating Silverlight Project

Adding parameters

Open the "InitializingParametersTestPage.aspx" and find the tag tag  <asp:Silverlight  add an attribute InitParameters
Enter the following code to the tag

InitParameters="Key1=Value1,Key2=Value2"

Defining the Parameters

In App.xaml.cs add an object of IDictionary<string,string> as follows

public IDictionary<string, string> AppParams;
In Application_Startup event initialize the parameters as follows
private void Application_Startup(object sender, StartupEventArgs e)
        {
            AppParams = e.InitParams;
            this.RootVisual = new Page();
        }

Using Parameters

In Page.xaml add ListBoxes to show the parameter values
Xaml Code

<UserControl x:Class="InitializingParameters.Page"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Width="400" Height="300">
    <Grid x:Name="LayoutRoot" Background="#FFB7C2E5">
                <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="0.472*"/>
                                <ColumnDefinition Width="0.025*"/>
                                <ColumnDefinition Width="0.502*"/>
                </Grid.ColumnDefinitions>
        <ListBox x:Name="myKeysList"/>
        <ListBox x:Name="myValuesList" Grid.Column="2"/>
    </Grid>
</UserControl>

In code behind of the Page.xaml.cs add the following code to bind the parameters

namespace InitializingParameters
{
    public partial class Page : UserControl
    {
        public Page()
        {
            InitializeComponent();
            App myApp = App.Current as App;

            foreach (string item in myApp.AppParams.Keys)
            {
                myKeysList.Items.Add(item);
            }
            foreach (string item1 in myApp.AppParams.Values)
            {
                myValuesList.Items.Add(item1);
            }
        }
    }
}

Runnning the Application

When you run the application the list will carry the key and value pairs.



Figure 1.2 Displaying Key Value pair

Hope you like the article, Enjoy Coding.