，欢迎访问网页设计爱好者web开发。前些日子在论坛上发了个帖子，100分寻求“橡皮条”法绘图的代码。效果不是很好，于是自己参照网友给的代码重新写了一个，解决了绘图与重绘的问题。由于只写了部分，所以功能有限，同时可能算法不是很好，希望大家指点！！窗体中仅包含一个pictruebox1,先将代码付诸于下：
using system;
using system.drawing;
using system.collections;
using system.componentmodel;
using system.windows.forms;
using system.data;
using system.drawing.drawing2d;
namespace gdi_练习
{
/// <summary>
/// form1 的摘要说明。
/// </summary>
public class form1 : system.windows.forms.form
{
public system.windows.forms.picturebox picturebox1;
private point p1 = point.empty, p2 = point.empty;
private bool ismousedown = false, ismouseup = false;
arraylist addarray = new arraylist();
public struct sharptype
{
public string type;
public point p1, p2;
public color forecolor, backcolor;
public brush brush;
public sharptype( string type, point p1, point p2, color forecolor, color backcolor, brush brush )
{
this.type = type;
this.p1 = p1;
this.p2 = p2;
this.forecolor = forecolor;
this.backcolor = backcolor;
this.brush = brush;
}
}
/// <summary>
/// 必需的设计器变量。
/// </summary>
private system.componentmodel.container components = null;
public form1()
{
//
// windows 窗体设计器支持所必需的
//
initializecomponent();
//
// todo: 在 initializecomponent 调用后添加任何构造函数代码
//
}
/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
protected override void dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.dispose();
}
}
base.dispose( disposing );
}
#region windows 窗体设计器生成的代码
/// <summary>
/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
/// </summary>
private void initializecomponent()
{
this.picturebox1 = new system.windows.forms.picturebox();
this.suspendlayout();
//
// picturebox1
//
this.picturebox1.backcolor = system.drawing.color.white;
this.picturebox1.dock = system.windows.forms.dockstyle.fill;
this.picturebox1.location = new system.drawing.point(0, 0);
this.picturebox1.name = "picturebox1";
this.picturebox1.size = new system.drawing.size(432, 397);
this.picturebox1.tabindex = 0;
this.picturebox1.tabstop = false;
this.picturebox1.paint += new system.windows.forms.painteventhandler(this.picturebox1_paint);
this.picturebox1.mouseup += new system.windows.forms.mouseeventhandler(this.picturebox1_mouseup);
this.picturebox1.mousemove += new system.windows.forms.mouseeventhandler(this.picturebox1_mousemove);
this.picturebox1.mousedown += new system.windows.forms.mouseeventhandler(this.picturebox1_mousedown);
//
// form1
//
this.autoscalebasesize = new system.drawing.size(6, 14);
this.clientsize = new system.drawing.size(432, 397);
this.controls.add(this.picturebox1);
this.name = "form1";
this.text = "form1";
this.resumelayout(false);
}
#endregion
/// <summary>
/// 应用程序的主入口点。
/// </summary>
[stathread]
static void main()
{
application.run(new form1());
}
private void picturebox1_mousedown(object sender, system.windows.forms.mouseeventargs e)
{
if( ! ismouseup )
{
this.ismousedown = true;
this.p1 = new point( e.x, e.y );
}
}
private void picturebox1_mousemove(object sender, system.windows.forms.mouseeventargs e)
{
graphics g = this.picturebox1.creategraphics();
if( ismousedown && p2 != point.empty )
g.drawellipse( pens.white, p1.x, p1.y, math.abs( p1.x - p2.x ), math.abs( p1.y - p2.y ) );
if( ismousedown && ! ismouseup )
{
p2 = new point( e.x, e.y );
g.drawellipse( pens.black, p1.x, p1.y, math.abs( p1.x - p2.x ), math.abs( p1.y - p2.y ) );
}
foreach( sharptype type in addarray )
{
g.drawellipse( pens.black, type.p1.x, type.p1.y, math.abs( type.p1.x - type.p2.x ), math.abs( type.p1.y - type.p2.y ) );
}
g.dispose();
}
private void picturebox1_mouseup(object sender, system.windows.forms.mouseeventargs e)
{
this.ismousedown = false;
p2 = new point( e.x, e.y );
graphics g = this.picturebox1.creategraphics();
g.drawellipse( pens.black, p1.x, p1.y, math.abs( p1.x - p2.x ), math.abs( p1.y - p2.y ) );
addarray.add( new sharptype( "a", p1, p2, color.black, color.empty, brushes.black ) );
p1 = point.empty;
p2 = point.empty;
g.dispose();
}
private void picturebox1_paint(object sender, system.windows.forms.painteventargs e)
{
foreach( sharptype type in addarray )
{
e.graphics.drawellipse( pens.black, type.p1.x, type.p1.y, math.abs( type.p1.x - type.p2.x ), math.abs( type.p1.y - type.p2.y ) );
}
}
}
}
