silverlight beta2 刚出来不久,变化很大,sdk里面的例子也不是很丰富

下面简单用托管代码写了一个小demo来实现手写功能,(SDK上面有个用js写的),效果如下:


准备:
安装
Install Visual Studio 2008
Install Silverlight Tools Beta 2 for Visual Studio 2008

新建一个silverlight工程。
在xaml页面加入一个InkPresenter 控件,这个例子主要是对InkPresenter控件进行操作
把下面代码复制到xaml页面
 <Grid x:Name="LayoutRoot" Background="BlueViolet">
        
<StackPanel>
<InkPresenter x:Name="inkCanvas"  Width="300" Height="200" Margin="50" MouseLeftButtonDown="inkCanvas_MouseLeftButtonDown" Background="Khaki"  MouseMove="inkCanvas_MouseMove" MouseLeftButtonUp="inkCanvas_MouseLeftButtonUp" MouseLeave="inkCanvas_MouseLeave">
            


        
</InkPresenter>
           
                
<Button x:Name="btnInk" Content="画笔"  Width="50" Height="20"  Click="btnInk_Click"></Button>
            
<Button x:Name="btnErase" Content="橡皮"  Width="50" Height="20" Click="btnErase_Click"></Button>    
       
</StackPanel>
    
</Grid>

下面就是通过写c#代码来操作了
注意到上面的InkPresenter控件里面有操作鼠标的方法,下面我们一个一个说
第一个方法inkCanvas_MouseLeftButtonDown
当鼠标左键按下去的时候开始取得当前坐标开始划线,这个方法的代码如下:
    private void inkCanvas_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        
{
            inkCanvas.CaptureMouse();
            Point p 
= e.GetPosition(inkCanvas);
            StylusPoint sp 
= new StylusPoint();
            sp.X 
= p.X;
            sp.Y 
= p.Y;
            
if (_isErase)//判断是不是橡皮
            {
                _epoint 
= new StylusPointCollection();
                _epoint.Add(sp);
              
            }

            
else
            
{
                _stroke 
= new Stroke();
                _stroke.StylusPoints.Add(e.StylusDevice.GetStylusPoints(inkCanvas));
                _stroke.DrawingAttributes 
= new DrawingAttributes();
//属性赋值
                _stroke.DrawingAttributes.Color = Colors.Black;
                _stroke.DrawingAttributes.Width 
= 2.00;
                _stroke.DrawingAttributes.Height 
= 2.00;
                _stroke.DrawingAttributes.OutlineColor 
= Colors.Green;
                inkCanvas.Strokes.Add(_stroke);
            
            }

        }
写完这个方法以后,当鼠标左键点击的时候就会往页面上画点。那么我们怎么移动画线呢,写mousemove事件inkCanvas_MouseMove,代码如下
    private void inkCanvas_MouseMove(object sender, MouseEventArgs e)
        
{
            Point p 
= e.GetPosition(inkCanvas);
          
            StylusPoint sp 
= new StylusPoint();
            sp.X 
= p.X;
            sp.Y 
= p.Y;
//也可以用  
// e.StylusDevice.GetStylusPoints(inkCanvas)
//来得到
            if (_isErase)
            
{
                
if (_epoint != null)
                
{

                    _epoint.Add(sp);
                    StrokeCollection sc 
= inkCanvas.Strokes.HitTest(_epoint);
                    
for (int i = 0; i < sc.Count; i++)
                    
{
                        
this.inkCanvas.Strokes.Remove(sc[i]);
                    }

                }

            }

            
else
            
{
                
if (_stroke != null)
                
{
                    _stroke.StylusPoints.Add(sp);
                }

            }

        }
最后一步实现鼠标左键松开的事件inkCanvas_MouseLeftButtonUp
  private void inkCanvas_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        
{
            
if (_stroke != null)
            
{
             Point pos 
= e.GetPosition(inkCanvas);
                StylusPoint sp 
= new StylusPoint();
                sp.X 
= pos.X;
                sp.Y 
= pos.Y;
                _stroke.StylusPoints.Add(sp);
            }

            
this.inkCanvas.ReleaseMouseCapture();
            _stroke 
= null;
            _epoint 
= null;
        }
大概就这样,大家根据这个进行扩展就行了
完整的代码我发到这个帖子里面了
http://bbs.crfly.com/showtopic-6552.aspx
posted on 2008-06-17 18:35  Duan Junyi   阅读(534)  评论(0编辑  收藏  举报