C#在进度条中显示复制文件的进度

1. using System; 
2. using System.Collections.Generic; 
3. using System.ComponentModel; 
4. using System.Data; 
5. using System.Drawing; 
6. using System.Linq; 
7. using System.Text; 
8. using System.Windows.Forms; 
9. using System.IO; 
10. using System.Xml; 
11. using System.Collections; 
12. using System.Reflection; 
13. using System.Threading; 
14.  
15. namespace CopyForm 
16. { 
17.     public partial class frmMain : Form 
18.     { 
19.         int totalSize; 
20.         int position; 
21.         const int BUFFER_SIZE = 4096; 
22.         byte buffer; 
23.         Stream stream; 
24.  
25.         public frmMain() 
26.         { 
27.             InitializeComponent(); 
28.         } 
29.  
30.         private void frmMain_Load(object sender, EventArgs e) 
31.         { 
32.         } 
33.  
34.         private void btnCopy_Click(object sender, EventArgs e) 
35.         { 
36.             string strFile = ""; 
37.             OpenFileDialog dlg = new OpenFileDialog(); 
38.             if (dlg.ShowDialog() == DialogResult.OK) 
39.             { 
40.                 strFile = dlg.FileName; 
41.             } 
42.             else 
43.             { 
44.                 return; 
45.             } 
46.  
47.             FileStream fs = new FileStream(strFile, FileMode.Open, FileAccess.Read); 
48.             totalSize = (int)fs.Length; 
49.             stream = fs; 
50.  
51.             //Delete file which aready exists. 
52.             if (File.Exists("c:\\CopyFile.bin")) 
53.             { 
54.                 File.Delete("c:\\CopyFile.bin"); 
55.             } 
56.  
57.             //Copy file while larger than 4KB. 
58.             if (totalSize > BUFFER_SIZE) 
59.             { 
60.                 buffer = new byte[BUFFER_SIZE]; 
61.  
62.                 // Async Invoke 
63.                 stream.BeginRead(buffer, 0, BUFFER_SIZE, new AsyncCallback(AsyncCopyFile), null); 
64.                 MessageBox.Show("文件拷贝完毕！"); 
65.             } 
66.             else 
67.             { 
68.                 fs.Close(); 
69.             } 
70.         } 
71.  
72.         /// <summary> 
73.         /// Asynchronously copy file 
74.         /// </summary> 
75.         /// <param name="ar"></param> 
76.         private void AsyncCopyFile(IAsyncResult ar) 
77.         { 
78.             int readenLength; 
79.  
80.             //Lock FileStream 
81.             lock (stream) 
82.             { 
83.                 // When stream endread, get readed length 
84.                 readenLength = stream.EndRead(ar); 
85.             } 
86.  
87.             // Write to disk 
88.             FileStream fsWriter = new FileStream("c:\\CopyFile.bin", FileMode.Append, FileAccess.Write); 
89.             fsWriter.Write(buffer, 0, buffer.Length); 
90.             fsWriter.Close(); 
91.  
92.             // Current stream position  
93.             position += readenLength; 
94.          
95.             // Response UI 
96.             MethodInvoker m = new MethodInvoker(SynchProgressBar); 
97.             m.BeginInvoke(null, null); 
98.  
99.             if (position >= totalSize)  //read over 
100.             { 
101.                 stream.Close(); 
102.                 return; 
103.             } 
104.  
105.             // Continue to read and write 
106.             lock (stream) 
107.             { 
108.                 int leftSize = totalSize - position; 
109.  
110.                 if (leftSize < BUFFER_SIZE) 
111.                 { 
112.                     buffer = new byte[leftSize]; 
113.                 } 
114.                 stream.BeginRead(buffer, 0, buffer.Length, new AsyncCallback(AsyncCopyFile), null); 
115.             } 
116.         } 
117.  
118.         private void SynchProgressBar() 
119.         { 
120.             this.progressBar1.Minimum = 0; 
121.             //this.progressBar1.Maximum = totalSize; 
122.             //this.progressBar1.Value = position; 
123.             SetControlPropertyValue(this.progressBar1, "Maximum", totalSize); 
124.             SetControlPropertyValue(this.progressBar1, "Value", position); 
125.         } 
126.  
127.         /// <summary> 
128.         /// Cross-thread operation not valid: (solution key) 
129.         /// Control 'progressBar1' accessed from a thread other than the thread it was created on 
130.         /// </summary> 
131.         /// <param name="oControl"></param> 
132.         /// <param name="propName"></param> 
133.         /// <param name="propValue"></param> 
134.         delegate void SetControlValueCallback(Control oControl, string propName, object propValue); 
135.         private void SetControlPropertyValue(Control oControl, string propName, object propValue) 
136.         { 
137.             if (oControl.InvokeRequired) 
138.             { 
139.                 SetControlValueCallback d = new SetControlValueCallback(SetControlPropertyValue); 
140.                 oControl.Invoke(d, new object { oControl, propName, propValue }); 
141.             } 
142.             else 
143.             { 
144.                 Type t = oControl.GetType(); 
145.                 PropertyInfo props = t.GetProperties(); 
146.                 foreach (PropertyInfo p in props) 
147.                 { 
148.                     if (p.Name.ToUpper() == propName.ToUpper()) 
149.                     { 
150.                         p.SetValue(oControl, propValue, null); 
151.                     } 
152.                 } 
153.             } 
154.         } 
155.  
156.         private void btnExit_Click(object sender, EventArgs e) 
157.         { 
158.             Application.Exit(); 
159.         } 
160.  
161.         private void frmMain_FormClosed(object sender, FormClosedEventArgs e) 
162.         { 
163.             GC.Collect(); 
164.             GC.WaitForPendingFinalizers(); 
165.         } 
166.     } 
167. }