学步园

 DrawRectangle.cs//画矩形的类using System;<br /> using System.Collections.Generic;<br /> using System.Text;<br /> using System.Drawing;<br /> using System.Drawing.Drawing2D;<br /> namespace wndApp.Code<br /> {<br /> class DrawRectangle<br /> {<br /> public Point location;//屏幕上点的坐标<br /> public Size size;//有长和宽的矩形<br /> public Color foreColor;//前景色,以上全部是一个结构体<br /> public Color backColor;//背景色<br /> /// <summary><br /> /// 画矩形的类的构造函数<br /> /// </summary><br /> /// <param name="initSize">初始大小</param><br /> /// <param name="initForeColor">初始前景色</param><br /> /// <param name="initBackColor">初始背景色</param><br /> public DrawRectangle(Size initSize, Color initForeColor, Color initBackColor)<br /> {<br /> size = initSize;<br /> foreColor = initForeColor;<br /> backColor = initBackColor;<br /> location = new Point(10, 10);//结构的new与类的new有区别,这里就是给结构内字段赋值了.<br /> }<br /> /// <summary><br /> /// 在指定窗体上画矩形<br /> /// </summary><br /> /// <param name="winHandle">窗体句柄,是一个结构体</param><br /> public void Draw(System.IntPtr winHandle)<br /> {<br /> Graphics g = Graphics.FromHwnd(winHandle);//从窗口句柄载入<br /> GraphicsPath gp = new GraphicsPath();//Drawing2D空间<br /> Rectangle rec = new Rectangle(location, size);<br /> gp.AddRectangle(rec);<br /> Color[] surroundColor = new Color[] { backColor };<br /> PathGradientBrush pb = new PathGradientBrush(gp);//渐变<br /> pb.CenterColor = foreColor;<br /> pb.SurroundColors = surroundColor;<br /> g.FillPath(pb, gp);//参数，效果和路径<br /> }<br /> /// <summary><br /> /// 擦除指定窗体中的方块<br /> /// </summary><br /> /// <param name="winHandle"></param><br /> public void Erase(System.IntPtr winHandle)<br /> {<br /> Graphics g = Graphics.FromHwnd(winHandle);<br /> Rectangle rec = new Rectangle(location, size);<br /> g.FillRectangle(new SolidBrush(Color.Red), rec);<br /> }<br /> }<br /> } 调用的方法:using System;<br /> using System.Collections.Generic;<br /> using System.ComponentModel;<br /> using System.Data;<br /> using System.Drawing;<br /> using System.Text;<br /> using System.Windows.Forms;<br /> using System.Drawing.Drawing2D;<br /> using System.Media;<br /> namespace wndApp<br /> {<br /> public partial class FrmDrawRectangle : Form<br /> {<br /> SoundPlayer sound = new SoundPlayer();//播放默认的声音,如果指定声音文件则播放指定声音<br /> public FrmDrawRectangle()<br /> {<br /> InitializeComponent();<br /> }<br /> private void btnDraw_Click(object sender, EventArgs e)<br /> {<br /> sound.SoundLocation = "FinishOneLine.wav";<br /> sound.Play();<br /> }<br /> //按钮的重绘事件<br /> private void btnDraw_Paint(object sender, PaintEventArgs e)<br /> {<br /> Size size = new Size(50, 50);<br /> Code.DrawRectangle rec = new Code.DrawRectangle(size,Color.Green,Color.Gold);<br /> rec.Draw(this.pBoxMain.Handle);//PictureBox窗口句柄<br /> }<br /> private void btnKey_Click(object sender, EventArgs e)<br /> {<br /> FrmKeyDown key = new FrmKeyDown();<br /> key.Show();<br /> }<br /> //Label的重绘事件,Text的改变不用刷新,图像的改变需要刷新<br /> private void lblDraw_Paint(object sender, PaintEventArgs e)<br /> {<br /> Graphics gp = e.Graphics;<br /> //gp.Clear(Color.Black);//不清除的话,则在原来图像上添加<br /> Pen p = new Pen(Color.Red);<br /> gp.DrawLine(p, 1, 30, 150, 30);<br /> }<br /> //调用Label的Paint事件<br /> //引发Button的单击事件<br /> private void btnReDraw_Click(object sender, EventArgs e)<br /> {<br /> Size size = new Size(50, 50);<br /> Code.DrawRectangle rec = new Code.DrawRectangle(size, Color.Green, Color.Gold);<br /> rec.Draw(this.lblDraw.Handle);<br /> //lblDraw.Invalidate();//调用Paint重绘,一重绘就会清除原来的所有图像,更新画布.<br /> btnKey.PerformClick();//引发Button的单击事件<br /> }<br /> }<br /> } end这里还有些知识点不清晰,先保存.