C# 带进度条的文件下载
原创
©著作权归作者所有：来自51CTO博客作者zhang51net的原创作品，请联系作者获取转载授权，否则将追究法律责任
1 private long fileLength;
2
3 private long downLength;//已经下载文件大小，外面想用就改成公共属性
4
5 private static bool stopDown;
6
7 public HttpDownLoad()
8
9 {
10
11 fileLength = 0;
12
13 downLength = 0;
14
15 stopDown = false;
16
17 //
18
19 // TODO: 在此处添加构造函数逻辑
20
21 //
22
23 }
24
25
26
27 /// <summary>
28
29 /// 文件下载
30
31 /// </summary>
32
33 /// <param name= "url "> 连接 </param>
34
35 /// <param name= "fileName "> 本地保存文件名 </param>
36
37 /// <param name= "progressBar "> 进度条 </param>
38
39 public void httpDownFile(string url, string fileName, ProgressBar progressBar)
40
41 {
42
43 Label lable = new Label();
44
45 httpDownFile(url, fileName, progressBar, lable);
46
47 lable.Dispose();
48
49 }
50
51
52
53 /// <summary>
54
55 /// 文件下载
56
57 /// </summary>
58
59 /// <param name= "url "> 连接 </param>
60
61 /// <param name= "fileName "> 本地保存文件名 </param>
62
63 /// <param name= "progressBar "> 进度条 </param>
64
65 /// <param name= "label "> 返回已经下载的百分比 </param>
66
67 public string httpDownFile(string url, string fileName, ProgressBar progressBar, Label label)
68
69 {
70
71 string strState = "No";
72
73 stopDown = false;
74
75 Stream str = null, fs = null;
76
77 try
78
79 {
80
81 //获取下载文件长度
82
83 fileLength = getDownLength(url);
84
85 downLength = 0;
86
87 if (fileLength > 0)
88
89 {
90
91 WebClient DownFile = new WebClient();
92
93 str = DownFile.OpenRead(url);
94
95 //判断并建立文件
96
97 if (createFile(fileName))
98
99 {
100
101 byte[] mbyte = new byte[1024];
102
103 int readL = str.Read(mbyte, 0, 1024);
104
105 fs = new FileStream(fileName, FileMode.OpenOrCreate, FileAccess.Write);
106
107 //读取流
108
109 while (readL != 0)
110
111 {
112
113 if (stopDown)
114
115 break;
116
117 downLength += readL;//已经下载大小
118
119 fs.Write(mbyte, 0, readL);//写文件
120
121 readL = str.Read(mbyte, 0, 1024);//读流
122
123 progressBar.Value = (int)(downLength * 100 / fileLength);
124
125 label.Text = progressBar.Value.ToString() + "% ";
126
127 Application.DoEvents();
128
129 strState = "OK";
130
131 }
132
133 str.Close();
134
135 fs.Close();
136
137 }
138
139 }
140
141 }
142
143 catch (Exception)
144
145 {
146
147 if (str != null)
148
149 str.Close();
150
151 if (fs != null)
152
153 fs.Close();
154
155 }
156
157 return strState;
158
159 }
160
161
162
163 /// <summary>
164
165 /// 文件下载
166
167 /// </summary>
168
169 /// <param name= "url "> 连接 </param>
170
171 /// <param name= "fileName "> 本地保存文件名 </param>
172
173 public void httpDownFile(string url, string fileName)
174
175 {
176
177 try
178
179 {
180
181 WebClient DownFile = new WebClient();
182
183 DownFile.DownloadFile(url, fileName);
184
185 }
186
187 catch (Exception)
188
189 {
190
191 //MessageBox.Show(ex.Message);
192
193 }
194
195 }
196
197
198
199 /// <summary>
200
201 /// 获取下载文件大小
202
203 /// </summary>
204
205 /// <param name= "url "> 连接 </param>
206
207 /// <returns> 文件长度 </returns>
208
209 private long getDownLength(string url)
210
211 {
212
213 try
214
215 {
216
217 WebRequest wrq = WebRequest.Create(url);
218
219 WebResponse wrp = (WebResponse)wrq.GetResponse();
220
221 wrp.Close();
222
223 return wrp.ContentLength;
224
225 }
226
227 catch (Exception)
228
229 {
230
231 //MessageBox.Show(ex.Message);
232
233 return 0;
234
235 }
236
237 }
238
239
240
241 /// <summary>
242
243 /// 建立文件(文件如已经存在，删除重建)
244
245 /// </summary>
246
247 /// <param name= "fileName "> 文件全名(包括保存目录) </param>
248
249 /// <returns> </returns>
250
251 private bool createFile(string fileName)
252
253 {
254
255 try
256
257 {
258
259 if (File.Exists(fileName))
260
261 {
262
263 File.Delete(fileName);
264
265 }
266
267 Stream s = File.Create(fileName);
268
269 s.Close();
270
271 return true;
272
273 }
274
275 catch (Exception)
276
277 {
278
279 //MessageBox.Show(ex.Message);
280
281 return false;
282
283 }
284
285 }
286
287
288
289 public void downClose()
290
291 {
292
293 stopDown = true;
294 }
