在开发Winform程序的时候，经常会用到等待窗口（如网络通讯、数据库连接等需要一定时间来执行的操作），这样可以给用户提供更好的体验。
等待窗口的主要功能是一边执行需要等待的操作，一边显示一个等待界面。当执行完毕时等待界面消失。用户可以提前取消操作，还可以设置操作的最大等待时间，若超过指定时间仍没完成操作可结束当前操作。等待窗口的操作处理内容可用λ表达式，在后面的应用实例中可看到使用方法。
实现界面如下图：
等待界面主要包含的部分：
- 等待图片；
- 等待消息文字("正在处理数据，请稍后...")：可自定义；
- 计时器：可设置不显示；
- 取消返回按钮：可设置不显示；
- 另外等待窗口显示和关闭的时候都有渐变的一个简单特效，等待窗口的颜色是在一定范围内随即的。
等待窗口实现代码：
|
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
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
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 WinForm_Test{ public partial class frmWaitingBox : Form { #region Properties private int _MaxWaitTime; private int _WaitTime; private bool _CancelEnable; private IAsyncResult _AsyncResult; private EventHandler<EventArgs> _Method; private bool _IsShown = true; private readonly int _EffectCount = 10; private readonly int _EffectTime = 500; /// <summary> /// 控制界面显示的特性 /// </summary> private Timer _Timer; public string Message { get; private set; } public int TimeSpan { get; set; } public bool FormEffectEnable { get; set; } #endregion #region frmWaitingBox public frmWaitingBox(EventHandler<EventArgs> method,int maxWaitTime,string waitMessage,bool cancelEnable,bool timerVisable) { maxWaitTime *= 1000; Initialize(method, maxWaitTime,waitMessage, cancelEnable, timerVisable); } public frmWaitingBox(EventHandler<EventArgs> method) { int maxWaitTime=60*1000; string waitMessage = "正在处理数据，请稍后..."; bool cancelEnable=true; bool timerVisable=true; Initialize(method, maxWaitTime,waitMessage, cancelEnable, timerVisable); } public frmWaitingBox(EventHandler<EventArgs> method, string waitMessage) { int maxWaitTime = 60 * 1000; bool cancelEnable = true; bool timerVisable = true; Initialize(method, maxWaitTime, waitMessage, cancelEnable, timerVisable); } public frmWaitingBox(EventHandler<EventArgs> method, bool cancelEnable, bool timerVisable) { int maxWaitTime = 60*1000; string waitMessage = "正在处理数据，请稍后..."; Initialize(method, maxWaitTime,waitMessage, cancelEnable, timerVisable); } #endregion #region Initialize private void Initialize(EventHandler<EventArgs> method, int maxWaitTime,string waitMessage,bool cancelEnable, bool timerVisable) { InitializeComponent(); //initialize form this.FormBorderStyle = FormBorderStyle.None; this.StartPosition = FormStartPosition.CenterParent; this.ShowInTaskbar = false; Color[] c = GetRandColor(); this.panel1.BackColor = c[0]; this.BackColor = c[1]; this.labMessage.Text = waitMessage; _Timer = new Timer(); _Timer.Interval = _EffectTime/_EffectCount; _Timer.Tick += _Timer_Tick; this.Opacity = 0; FormEffectEnable = true; //para TimeSpan = 500; Message = string.Empty; _CancelEnable = cancelEnable; _MaxWaitTime = maxWaitTime; _WaitTime = 0; _Method = method; this.pictureBoxCancel.Visible = _CancelEnable; this.labTimer.Visible = timerVisable; this.timer1.Interval = TimeSpan; this.timer1.Start(); } #endregion #region Color private Color[] GetRandColor() { int rMax = 248; int rMin = 204; int gMax = 250; int gMin = 215; int bMax = 250; int bMin = 240; Random r = new Random(DateTime.Now.Millisecond); int r1 = r.Next(rMin, rMax); int r2 = r1 + 5; int g1 = r.Next(gMin, gMax); int g2 = g1 + 5; int b1 = r.Next(bMin, bMax); int b2 = b1 + 5; Color c1 = Color.FromArgb(r1, g1, b1); Color c2 = Color.FromArgb(r2, g2, b2); Color[] c = { c1, c2 }; return c; } #endregion #region Events private void btnCancel_Click(object sender, EventArgs e) { this.Message = "您结束了当前操作！"; this.Close(); } private void timer1_Tick(object sender, EventArgs e) { _WaitTime += TimeSpan; this.labTimer.Text = string.Format("{0}秒", _WaitTime / 1000); if (!this._AsyncResult.IsCompleted) { if (_WaitTime > _MaxWaitTime) { Message = string.Format("处理数据超时{0}秒，结束当前操作！", _MaxWaitTime / 1000); this.Close(); } } else { this.Message = string.Empty; this.Close(); } } private void frmWaitingBox_Shown(object sender, EventArgs e) { _AsyncResult = _Method.BeginInvoke(null, null, null, null); //Effect if (FormEffectEnable) { _Timer.Start(); } else this.Opacity = 1; } private void frmWaitingBox_FormClosing(object sender, FormClosingEventArgs e) { if (FormEffectEnable) { if(this.Opacity>=1) e.Cancel = true; _Timer.Start(); } } private void _Timer_Tick(object sender, EventArgs e) { if (_IsShown) { if (this.Opacity >= 1) { _Timer.Stop(); _IsShown = false; } this.Opacity += 1.00 / _EffectCount; } else { if (this.Opacity <= 0) { _Timer.Stop(); _IsShown = true; this.Close(); } this.Opacity -= 1.00 / _EffectCount; } } #endregion }} |
应用实例代码：
|
1
2
3
4
5
6
7
8
9
10
11
12
|
string res; DataTable dt=null; frmWaitingBox f = new frmWaitingBox((obj,args)=> { Thread.Sleep(5000); string sql = "SELECT * FROM [test].[dbo].[studentInfo]"; SQLHelper sqlHelper=new SQLHelper(); dt = sqlHelper.ExecuteSqlStr(sql,out res); }); f.ShowDialog(this); dataGridView1.DataSource = dt; |
源码下载：下载地址——（http://files.cnblogs.com/anding/WinForm_Test1.rar）
原文地址:http://www.cnblogs.com/anding/archive/2010/10/07/1845251.html