最近做一个图象的采集，需要一个图形的选择控件，但是在.net下没有类似vb中的shape控件，所以考虑了自己写一个控件。
下面我将从头创建控件，这个控件主要是用来选择图形的Rectangle，有一下几个属性Color BorderColor：边框颜色，Color BackColor：背景颜色，bool ReSizeble：是否可移动， Rectangle SelectRectangle：选择区域。
打开vs2003（我用的这个版本），新建一个c#控件库，ok，拷贝如下代码到你的代码里。
using System;
using System.Collections;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Windows.Forms;
namespace WindowsExtendedControls
{
/// <summary>
/// 控件
/// </summary>
public class ShapeEx : System.Windows.Forms.Control
{
/// <summary>
/// 必需的设计器变量。
/// </summary>
///
private Color _BorderColor=new Color(,',',');
private Color _BackColor=new Color(,',',');
private bool _ReSizeble;
private Point _SelfLocation=new Point(,',',');
private Point _MouseLocation=new Point(,',',');
private int _SelfWidth;
private int _SelfHeight;
private int _SelectSelctedIndex;//0-8,0:SizeAll
private Rectangle _rectLeftSelector=new Rectangle(,',',');
private Rectangle _rectTopSelector=new Rectangle(,',',');
private Rectangle _rectRightSelector=new Rectangle(,',',');
private Rectangle _rectBottomSelector=new Rectangle(,',',');
private Rectangle _rectLeftTopSelector=new Rectangle(,',',');
private Rectangle _rectRightTopSelector=new Rectangle(,',',');
private Rectangle _rectRightBottomSelector=new Rectangle(,',',');
private Rectangle _rectLeftBottomSelector=new Rectangle(,',',');
private System.ComponentModel.Container components = null;
public ShapeEx()
{
// 该调用是 Windows.Forms 窗体设计器所必需的。
InitializeComponent(,',',');
// TODO: 在 InitComponent 调用后添加任何初始化
}
[DefaultValue("Black"),Description("边框颜色"),Category("Appearance")]
public Color BorderColor
{
get
{
// Insert code here.
return _BorderColor;
}
set
{
_BorderColor=value;
this.Invalidate(,',',');
}
}
[DefaultValue("Control"),Description("背景颜色"),Category("Appearance")]
public override Color BackColor
{
get
{
// Insert code here.
return _BackColor;
}
set
{
_BackColor=value;
this.Invalidate(,',',');
}
}
[DefaultValue(false),Description("运行中控件大小是否可拖拽编辑"),Category("Behavior")]
public bool ReSizeble
{
get
{
// Insert code here.
return _ReSizeble;
}
set
{
_ReSizeble=value;
this.Invalidate(,',',');
}
}
[Description("控件选择区域"),Category("Behavior")]
public Rectangle SelectRectangle
{
get
{
Rectangle selectRectangler=new Rectangle(,',',');
selectRectangler.X = this.Location.X+7;
selectRectangler.Y = this.Location.Y+7;
selectRectangler.Height = this.Height-15;
selectRectangler.Width = this.Width-15;
return selectRectangler;
}
}
protected override void OnPaint(PaintEventArgs pe)
{
// Calling the base class OnPaint
base.OnPaint(pe,',',');
ReDrawControl(pe.Graphics,',',');
}
private void DrawSelector(Graphics graphics)
{
SolidBrush SelectorPen=new SolidBrush(Color.White,',',');
Pen borderPen=new Pen(this._BorderColor,1,',',');
try
{
//实心
PointF[] LeftPoints=getPointF(0,this.Height/2-3,6,6,',',');
graphics.FillClosedCurve(SelectorPen, LeftPoints,',',');
PointF[] TopPoints=getPointF(this.Width/2-3,0,6,6,',',');
graphics.FillClosedCurve(SelectorPen, TopPoints,',',');
PointF[] RightPoints=getPointF(this.Width-7,this.Height/2-3,6,6,',',');
graphics.FillClosedCurve(SelectorPen, RightPoints,',',');
PointF[] BottomPoints=getPointF(this.Width/2-3,this.Height-7,6,6,',',');
graphics.FillClosedCurve(SelectorPen, BottomPoints,',',');
PointF[] LeftTopPoints=getPointF(0,0,6,6,',',');
graphics.FillClosedCurve(SelectorPen, LeftTopPoints,',',');
PointF[] RightTopPoints=getPointF(this.Width-7,0,6,6,',',');
graphics.FillClosedCurve(SelectorPen, RightTopPoints,',',');
PointF[] RightBottomPoints=getPointF(this.Width-7,this.Height-7,6,6,',',');
graphics.FillClosedCurve(SelectorPen, RightBottomPoints,',',');
PointF[] LeftBottomPoints=getPointF(0,this.Height-7,6,6,',',');
graphics.FillClosedCurve(SelectorPen, LeftBottomPoints,',',');
//边框
_rectLeftSelector.X = 0;
_rectLeftSelector.Y = this.Height/2-3;
_rectLeftSelector.Height = 6;
_rectLeftSelector.Width = 6;
graphics.DrawRectangle(borderPen, _rectLeftSelector,',',');
_rectTopSelector.X = this.Width/2-3;
_rectTopSelector.Y = 0;
_rectTopSelector.Height = 6;
_rectTopSelector.Width = 6;
graphics.DrawRectangle(borderPen, _rectTopSelector,',',');
_rectRightSelector.X = this.Width-7;
_rectRightSelector.Y = this.Height/2-3;
_rectRightSelector.Height = 6;
_rectRightSelector.Width = 6;
graphics.DrawRectangle(borderPen, _rectRightSelector,',',');
_rectBottomSelector.X = this.Width/2-3;
_rectBottomSelector.Y = this.Height-7;
_rectBottomSelector.Height = 6;
_rectBottomSelector.Width = 6;
graphics.DrawRectangle(borderPen, _rectBottomSelector,',',');
_rectLeftTopSelector.X=0;
_rectLeftTopSelector.Y=0;
_rectLeftTopSelector.Width=6;
_rectLeftTopSelector.Height=6;
graphics.DrawRectangle(borderPen, _rectLeftTopSelector,',',');
_rectRightTopSelector.X=this.Width-7;
_rectRightTopSelector.Y=0;
_rectRightTopSelector.Width=6;
_rectRightTopSelector.Height=6;
graphics.DrawRectangle(borderPen, _rectRightTopSelector,',',');
_rectRightBottomSelector.X=this.Width-7;
_rectRightBottomSelector.Y=this.Height-7;
_rectRightBottomSelector.Width=6;
_rectRightBottomSelector.Height=6;
graphics.DrawRectangle(borderPen, _rectRightBottomSelector,',',');
_rectLeftBottomSelector.X=0;
_rectLeftBottomSelector.Y=this.Height-7;
_rectLeftBottomSelector.Width=6;
_rectLeftBottomSelector.Height=6;
graphics.DrawRectangle(borderPen, _rectLeftBottomSelector,',',');
}
catch(Exception E)
{
throw E;
}
finally
{
SelectorPen.Dispose(,',',');
borderPen.Dispose(,',',');
}
}
private void ReDrawControl(Graphics graphics)
{
try
{
//绘制背景
/*
graphics.Clear(this._BackColor,',',');
SolidBrush backPen=new SolidBrush(this._BackColor,',',');
PointF point1 = new PointF(1,1,',',');
PointF point2 = new PointF(this.Width-2,1,',',');
PointF point3 = new PointF(this.Width-2,this.Height-2,',',');
PointF point4 = new PointF(1,this.Height-2,',',');
PointF[] points = {point1, point2, point3, point4};
graphics.FillClosedCurve(backPen, points,',',');
*/
//绘制边框
Rectangle rectBorder=new Rectangle(,',',');
Pen borderPen=new Pen(this._BorderColor,1,',',');
rectBorder.X = 7;
rectBorder.Y = 7;
rectBorder.Height = this.Height-15;
rectBorder.Width = this.Width-15;
graphics.DrawRectangle(borderPen, rectBorder,',',');
//绘制编辑框
if (_ReSizeble)
{
DrawSelector(graphics,',',');
}
}
catch(Exception E)
{
throw E;
}
finally
{
graphics.Dispose(,',',');
}
}
/// <summary>
/// 清理所有正在使用的资源。
/// </summary>
private PointF[] getPointF(int x,int y,int Width,int Height){
PointF point1 = new PointF(x,y,',',');
PointF point2 = new PointF(x+Width,y,',',');
PointF point3 = new PointF(x+Width,y+Height,',',');
PointF point4 = new PointF(x,y+Height,',',');
PointF[] points = {point1, point2, point3, point4};
return points;
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if( components != null )
components.Dispose(,',',');
}
base.Dispose( disposing ,',',');
}
#region 组件设计器生成的代码
/// <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()
{
components = new System.ComponentModel.Container(,',',');
this.Resize+=new EventHandler(ShapeEx_Resize,',',');
this.MouseDown+=new MouseEventHandler(ShapeEx_MouseDown,',',');
this.MouseMove+=new MouseEventHandler(ShapeEx_MouseMove,',',');
this.MouseLeave+=new EventHandler(ShapeEx_MouseLeave,',',');
this.MouseUp+=new MouseEventHandler(ShapeEx_MouseUp,',',');
this._BorderColor=Color.Black;
this._BackColor=Color.FromName("Control",',',');
this._ReSizeble=false;
this._SelectSelctedIndex=-1;
SetStyle(ControlStyles.SupportsTransparentBackColor, true,',',');
}
#endregion
private void ShapeEx_Resize(object sender, EventArgs e)
{
if (this.Width<16 || this.Height<16)
{
this.Width=16;
this.Height=16;
}
this.Invalidate(,',',');
}
private void ShapeEx_MouseDown(object sender, MouseEventArgs e)
{
if (_ReSizeble)
{
if (_rectLeftSelector.Contains(e.X,e.Y) ||
_rectRightSelector.Contains(e.X,e.Y) ||
_rectTopSelector.Contains(e.X,e.Y) ||
_rectBottomSelector.Contains(e.X,e.Y)
||_rectLeftTopSelector.Contains(e.X,e.Y) ||
_rectRightTopSelector.Contains(e.X,e.Y) ||
_rectRightBottomSelector.Contains(e.X,e.Y) ||
_rectLeftBottomSelector.Contains(e.X,e.Y))
{
if (_rectLeftTopSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeNWSE;
this._SelectSelctedIndex=1;
}
if (_rectTopSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeNS;
this._SelectSelctedIndex=2;
}
if (_rectRightTopSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeNESW;
this._SelectSelctedIndex=3;
}
if (_rectRightSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeWE;
this._SelectSelctedIndex=4;
}
if (_rectRightBottomSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeNWSE;
this._SelectSelctedIndex=5;
}
if (_rectBottomSelector.Contains(e.X,e.Y))
{
this.Cursor=Cursors.SizeNS;
this._SelectSelctedIndex=6;
}
if (_rectLeftBottomSelector.Contains(e.X,e.Y) )
{
this.Cursor=Cursors.SizeNESW;
this._SelectSelctedIndex=7;
}
if (_rectLeftSelector.Contains(e.X,e.Y))
{
this.Cursor=Cursors.SizeWE;
this._SelectSelctedIndex=8;
}
}
else
{
this.Cursor=Cursors.SizeAll;
this._SelectSelctedIndex=0;
}
this._SelfLocation.X=this.Location.X;
this._SelfLocation.Y=this.Location.Y;
this._MouseLocation.X=Cursor.Position.X;
this._MouseLocation.Y=Cursor.Position.Y;
this._SelfWidth=this.Width;
this._SelfHeight=this.Height;
}
}
private void ShapeEx_MouseMove(object sender, MouseEventArgs e)
{
//move and resize
switch (this._SelectSelctedIndex)
{
case 0:
this.Location=new
Point(Cursor.Position.X-(_MouseLocation.X-_SelfLocation.X),Cursor.Position.Y-(_MouseLocation.Y-_SelfLocation.Y),',',');
break;
case 1:
this.Height=this._SelfHeight-(Cursor.Position.Y-_MouseLocation.Y,',',');
this.Width=this._SelfWidth-(Cursor.Position.X-_MouseLocation.X,',',');
this.Location=new
Point(Cursor.Position.X-_MouseLocation.X+_SelfLocation.X,Cursor.Position.Y-_MouseLocation.Y+_SelfLocation.Y,',',');
break;
case 2:
this.Height=this._SelfHeight-(Cursor.Position.Y-_MouseLocation.Y,',',');
this.Location=new Point(_SelfLocation.X,Cursor.Position.Y-_MouseLocation.Y+_SelfLocation.Y,',',');
break;
case 3:
this.Height=this._SelfHeight-(Cursor.Position.Y-_MouseLocation.Y,',',');
this.Width=this._SelfWidth+(Cursor.Position.X-_MouseLocation.X,',',');
this.Location=new Point(_SelfLocation.X,Cursor.Position.Y-(_MouseLocation.Y-_SelfLocation.Y),',',');
break;
case 4:
this.Width=this._SelfWidth+(Cursor.Position.X-_MouseLocation.X,',',');
break;
case 5:
this.Height=this._SelfHeight+(Cursor.Position.Y-_MouseLocation.Y,',',');
this.Width=this._SelfWidth+(Cursor.Position.X-_MouseLocation.X,',',');
break;
case 6:
this.Height=this._SelfHeight+(Cursor.Position.Y-_MouseLocation.Y,',',');
break;
case 7:
this.Height=this._SelfHeight+(Cursor.Position.Y-_MouseLocation.Y,',',');
this.Width=this._SelfWidth-(Cursor.Position.X-_MouseLocation.X,',',');
this.Location=new Point(Cursor.Position.X-_MouseLocation.X+_SelfLocation.X,_SelfLocation.Y,',',');
break;
case 8:
this.Width=this._SelfWidth-(Cursor.Position.X-_MouseLocation.X,',',');
this.Location=new Point(Cursor.Position.X-_MouseLocation.X+_SelfLocation.X,_SelfLocation.Y,',',');
break;
}
}
private void ShapeEx_MouseLeave(object sender, EventArgs e)
{
this.Cursor=Cursors.Default;
this._SelectSelctedIndex=-1;
}
private void ShapeEx_MouseUp(object sender, MouseEventArgs e)
{
this.Cursor=Cursors.Default;
this._SelectSelctedIndex=-1;
}
}
}
下面讲一下控件具体如何工作，首先要写他的属性以及重写他的属性，
private Color _BorderColor=new Color(,',',');
[DefaultValue("Black"),Description("边框颜色"),Category("Appearance")]
public Color BorderColor
{
get
{
// Insert code here.
return _BorderColor;
}
set
{
_BorderColor=value;
this.Invalidate(,',',');
}
}
DefaultValue：设定默认值，Description：描述，就是属性下面的说明，Category：属性分类.其他的同理
设置好属性以后应该重写他的绘制过程，也就是
protected override void OnPaint(PaintEventArgs pe)
{
// Calling the base class OnPaint
base.OnPaint(pe,',',');
ReDrawControl(pe.Graphics,',',');
}
private void ReDrawControl(Graphics graphics)
{
try
{
//绘制边框
Rectangle rectBorder=new Rectangle(,',',');
Pen borderPen=new Pen(this._BorderColor,1,',',');
rectBorder.X = 7;
rectBorder.Y = 7;
rectBorder.Height = this.Height-15;
rectBorder.Width = this.Width-15;
graphics.DrawRectangle(borderPen, rectBorder,',',');
//绘制编辑框
if (_ReSizeble)
{
DrawSelector(graphics,',',');
}
}
catch(Exception E)
{
throw E;
}
finally
{
graphics.Dispose(,',',');
}
}
[Description("控件选择区域"),Category("Behavior")]
public Rectangle SelectRectangle
{
get
{
Rectangle selectRectangler=new Rectangle(,',',');
selectRectangler.X = this.Location.X+7;
selectRectangler.Y = this.Location.Y+7;
selectRectangler.Height = this.Height-15;
selectRectangler.Width = this.Width-15;
return selectRectangler;
}
}
ReDrawControl中定义了Rectangle （矩形），让后填充改矩形的边框：graphics.DrawRectangle(borderPen, rectBorder,',',');，这里要说明的是边框外面还有编辑框，所以大小不是控件的大小。DrawSelector就是绘制8个选择框的，基本和绘制边框差不多，即使定义好坐标就可以了。干好了之后不要忘了释放资源：graphics.Dispose(,',',');
SelectRectangle:控件所选择的Rectangle，最终要得就是它了
ok,这样一个基本的东西出来了，下面我们要写他的move和resize函数了，先添加事件:
this.Resize += new System.EventHandler(this.ShapeEx_Resize,',','); this.MouseUp += new System.Windows.Forms.MouseEventHandler(this.ShapeEx_MouseUp,',','); this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.ShapeEx_MouseMove,',','); this.MouseLeave += new System.EventHandler(this.ShapeEx_MouseLeave,',','); this.MouseDown += new System.Windows.Forms.MouseEventHandler(this.ShapeEx_MouseDown,',',');
原理：当鼠标点击的时候this.MouseDown,记录鼠标的位置，控件的原始位置和大小，判断位置：_rectLeftBottomSelector.Contains(e.X,e.Y)：表示点击的是左下，设置鼠标，记录状态this._SelectSelctedIndex：判断点击了那个选择框，取值0-8：0代表移动整个控件，1是右上移动，2－8顺时针索引选择框。this.MouseMove处理如何改变控件的大小和位置
case 0://只移动位置
this.Location=new Point(Cursor.Position.X-(_MouseLocation.X-_SelfLocation.X),Cursor.Position.Y-(_MouseLocation.Y-_SelfLocation.Y),',',');
break;
1，5不仅移动位置，还改变大小，2，3，4，6，7，8只改变大小
其他则是清理工作。
好了，那么赶紧编译。生成就可以了。
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