Creating a Silverlight Game-Part IV

In this concluding part of the article series, we will see how to add code in the event handler.

Note: The C# code given below may seem cumbersome to you and it's quite possible that you can develop a better version of it. You are welcome to implement the logic in your own way.

The XAML code for the button b1 in MainPage.xaml looks like this:

<Button x:Name="b1" Content=" " Grid.Column="0" Grid.Row="0" Style="{StaticResource ButtonStyle1}"  />

Similarly it would be seen for all the nine buttons.

Add an event handler to trap the Click event as follows:

<Button x:Name="b1" Content=" " Grid.Column="0" Grid.Row="0" Click="btnClick" Style="{StaticResource ButtonStyle1}"  />

This will auto-generate a Click event handler in the code-behind:

private void btnClick(object sender, RoutedEventArgs e)
{
}

Add code in this event handler as follows:

if (CheckGame())
{
      MessageBox.Show("Game over! you won");
      string newname, str, name;
      Button btn1, bn, btn;
      bn = (Button)e.OriginalSource;
      bn.Background = new SolidColorBrush(Colors.Yellow);
      str = bn.Content.ToString();
      name =  bn.Name; 
      int x = int.Parse(name.Substring(1)); 
      int[] arr = {1,2,4,5,7,8};
      if (arr.Contains(x))
      {
         if (CheckBlank(x+1))
         {
             btn = (Button)GridRoot.FindName(name); 
             btn.Content = " ";
             newname = "b"+(x+1);
             btn1 = (Button)GridRoot.FindName(newname); 
             btn1.Content = str;
         }
       }
      arr =  new int[]{2,3,5,6,9,8};
            if (arr.Contains(x))
            {
                if (CheckBlank(x - 1))
                {
                    btn = (Button)GridRoot.FindName(name);
                    btn.Content = " ";
                    newname = "b" + (x - 1);
                    btn1 = (Button)GridRoot.FindName(newname);
                    btn1.Content = str;
                }
             }
            arr = new int[] {1,2,3,4,5,6};
            if (arr.Contains(x))
            {
                if (CheckBlank(x + 3))
                {
                     btn = (Button)GridRoot.FindName(name);
                     btn.Content = " ";
                     newname = "b" + (x + 3);
                     btn1 = (Button)GridRoot.FindName(newname);
                     btn1.Content = str;
                }
            }
            arr = new int[] {4,5,6,7,8,9 };
            if (arr.Contains(x))
            {
                if (CheckBlank(x - 3))
                {
                     btn = (Button)GridRoot.FindName(name);
                    btn.Content = " ";
                     newname = "b" + (x -3);
                     btn1 = (Button)GridRoot.FindName(newname);
                    btn1.Content = str;
                }
            }
            if (CheckGame())
            {
                MessageBox.Show("Game over! you won");
            }
 }

The above code uses a pattern of numbers to check where the exchange between the blank cell and a filled cell should take place. To check whether the user clicked a particular cell, we make use of an array named arr and populate the numbers in it. Then we check whether the game is over by invoking a method CheckGame(). The code for this method is as follows:

private bool CheckGame()
{
    string newname;
    Button b=null;
    bool flag = true;
    for(int index=1; index <= 8;index++)
    {
        newname = "b" + index;
        b = (Button)GridRoot.FindName(newname);
        int val = 0;
        if (!b.Content.Equals (" "))
        {
             val = int.Parse(b.Content.ToString());
             if (val != index)
             {
                       flag = false;
             }
        }
        else
             flag = false;
    }
    if (flag)
    {
         return true;
    }
    else
         return false;
 }

Finally, the code for the method CheckBlank() is as follows:

private bool CheckBlank(int x)
{
     Button b=null;
     int i = 0;
     foreach (Control c in GridRoot.Children)
     {
         i++;
         b = (Button)c;
         if (b.Content.Equals(" "))
         {
            break;
         }
     }
     if (i == x)
         return true;
     else
         return false;
 }

Save, build and test the application.

Thus, you explored how to create a simple game using Silverlight and Blend. This example used very few effects and capabilities of Silverlight and Blend. If possible, try to implement lot more in your version of the code because both Silverlight and Blend have ample potential and powerful features.

Part I | Part II | Part III