本文实例讲述了C# WinForm实现窗体上控件自由拖动功能。分享给大家供大家参考,具体如下:
说明:首先在窗体上放一个PictrueBox控件,命名为pb1,拖动完整代码如下:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace WinFormDrag { public partial class Form1 : Form { //鼠标按下坐标(control控件的相对坐标) Point mouseDownPoint = Point.Empty; //显示拖动效果的矩形 Rectangle rect = Rectangle.Empty; //是否正在拖拽 bool isDrag = false ; public Form1() { InitializeComponent(); } private void Form1_Paint( object sender, PaintEventArgs e) { if (rect != Rectangle.Empty) { if (isDrag) { //画一个和Control一样大小的黑框 e.Graphics.DrawRectangle(Pens.Black, rect); } else { e.Graphics.DrawRectangle( new Pen( this .BackColor), rect); } } } /// <summary> /// 按下鼠标时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseDown( object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { mouseDownPoint = e.Location; //记录控件的大小 rect = pb1.Bounds; } } /// <summary> /// 移过时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseMove( object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { isDrag = true ; //重新设置rect的位置,跟随鼠标移动 rect.Location = getPointToForm( new Point(e.Location.X - mouseDownPoint.X, e.Location.Y - mouseDownPoint.Y)); this .Refresh(); } } /// <summary> /// 释放鼠标按钮时 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void pb1_MouseUp( object sender, MouseEventArgs e) { if (e.Button == MouseButtons.Left) { if (isDrag) { isDrag = false ; //移动control到放开鼠标的地方 pb1.Location = rect.Location; this .Refresh(); } reset(); } } //重置变量 private void reset() { mouseDownPoint = Point.Empty; rect = Rectangle.Empty; isDrag = false ; } //把相对与control控件的坐标,转换成相对于窗体的坐标。 private Point getPointToForm(Point p) { return this .PointToClient(pb1.PointToScreen(p)); } } } |
希望本文所述对大家C#程序设计有所帮助。