New Features of Silverlight 5 beta: 9. Video fast forward and fast return and TextSearch object query of text items

This section describes two new features: 1. In Silverlight 5, you can control the video played by the MediaElement object for fast forward and backward control. 2. Search and query the text items in Silverlight 5.

1. Fast-forward control of videos played by MediaElement Media

It is controlled through the MediaElement. PlaybackRate attribute. Currently, this attribute only supports seven parameters:-8.0,-4.0, 0.5, 1.0, 2.0, and 4.0, that is to say, it is 8 times faster, 4 times faster, 0.5 times slower, normal, 2 times faster, 4 times faster, and 8 times faster. Now let's take a look at the MediaElement object control source code in this instance as follows:

// Control the playback speed
Int flag = 0;
Private void button6_Click (object sender, RoutedEventArgs e)
{
If (flag = 0)
{
This. showVideo. PlaybackRate = 0.5;
}
Else if (flag = 1)
{
This. showVideo. PlaybackRate = 1.0;
}
Else if (flag = 2)
{
This. showVideo. PlaybackRate = 2.0;

}
Else if (flag = 3)
{
This. showVideo. PlaybackRate = 4.0;

}
Else if (flag = 4)
{
This. showVideo. PlaybackRate = 8.0;
Flag = 0;
Return;
}
Flag ++;
}

The effect preview is as follows:

2. TextSearch object query text items

It is a new TextSearch class added in Silverlight 5. Set TextSearch. TextPath = "FirstName" in all text controls with Item attributes (such as ComboBox and ListBox. Of course, FirstName is a field bound to the source class. The source code of XAML is as follows:

        <ListBox ItemsSource="{Binding}"               TextSearch.TextPath="FirstName"               Width="176"               Height="363"               HorizontalAlignment="Center"               VerticalAlignment="Center"               DisplayMemberPath="FirstName" Margin="610,31,214,106" />        <ComboBox ItemsSource="{Binding}"               TextSearch.TextPath="FirstName"               Width="137"               Height="30"               HorizontalAlignment="Center"               VerticalAlignment="Center"               DisplayMemberPath="FirstName" Margin="797,31,66,439" />

The following binding is required in the cs code:

      public partial class MainPage : UserControl
    {
public MainPage()
        {
            InitializeComponent();

            BindListData();
private void BindListData()
        {
            DataContext = new List<User>()
            {
new User()
                {
                    FirstName= "liusan",
                    Age=20
                },
new User()
                {
                    FirstName= "liyun",
                    Age=20
                },
new User()
                {
                    FirstName= "liulin",
                    Age=20
                },
new User()
                {
                    FirstName= "mingtian",
                    Age=20
                },
new User()
                {
                    FirstName= "jintian",
                    Age=20
                },
new User()
                {
                    FirstName= "shanghai",
                    Age=20
                },
new User()
                {
                    FirstName= "chengdu",
                    Age=20
                },
new User()
                {
                    FirstName= "luntai",
                    Age=20
                },
new User()
                {
                    FirstName= "shenming",
                    Age=20
                },
new User()
                {
                    FirstName= "edison",
                    Age=20
                },
new User()
                {
                    FirstName= "jeson",
                    Age=20
                },
new User()
                {
                    FirstName= "jiufen",
                    Age=20
                },
new User()
                {
                    FirstName= "jiuding",
                    Age=20
                },
new User()
                {
                    FirstName= "shenfenzheng",
                    Age=20
                }
            }.OrderBy(x => x.FirstName);
        }
    }

public class User
    {
public String FirstName
        {
get;
set;
        }
public Int32 Age
        {
get;
set;
        }
    }

Finally, when the focus is obtained in ComboBox or ListItem, you can press the English character on the keyboard to automatically find the corresponding Item. This example is written in VS2010 + Silverlight 5 beta. If you need the source code, click SLTextSearch.zip to download it. Now let's see the following: