因项目需要，要实现WinForm下的文件上传，个人觉得采用FTP方法太麻烦，还得配置FTP服务器，要通过防火墙也是一个麻烦。本来打算采用WebClient方法，但是采用这个方法实现后，进度条很短时间后就达到最大值，要等待一段时间才能传送完毕，要是文件太大（我这里测试约100M），会出现错误。后来才知道，原来WebClient是在加载完整个文件到内存后才真正开始上传，怪不得会出现前面的问题了。不得已参考了很多文章，老外的一个文章对我启发很大（http://blogs.msdn.com/johan/archive/2006/11/15/are-you-getting-outofmemoryexceptions-when-uploading-large-files.aspx），是采用HttpWebRequest方法实现的。废话少说，开始进入正题。实现过程如下：
在WinForm里面调用下面的方法来上传文件：
参数说明如下：
address：接收文件的URL地址，如：http://localhost/UploadFile/Save.aspx
fileNamePath：要上传的本地文件，如：D:/test.rar
saveName：文件上传到服务器后的名称，如：200901011234.rar
progressBar：显示文件上传进度的进度条。
/// <summary>
/// 将本地文件上传到指定的服务器(HttpWebRequest方法)
/// </summary>
/// <param name="address">文件上传到的服务器</param>
/// <param name="fileNamePath">要上传的本地文件（全路径）</param>
/// <param name="saveName">文件上传后的名称</param>
/// <param name="progressBar">上传进度条</param>
/// <returns>成功返回1，失败返回0</returns>
public int UploadFile(string address, string fileNamePath, string saveName, ProgressBarControl progressBar)
{
int returnValue = 0;
// 要上传的文件
FileStream fs = new FileStream(fileNamePath, FileMode.Open, FileAccess.Read);
BinaryReader r = new BinaryReader(fs);
//时间戳
string strBoundary = "----------" + DateTime.Now.Ticks.ToString("x");
byte[] boundaryBytes = Encoding.ASCII.GetBytes("\r\n--" + strBoundary + "\r\n");
//请求头部信息
StringBuilder sb = new StringBuilder();
sb.Append("--");
sb.Append(strBoundary);
sb.Append("\r\nContent-Disposition: form-data; name=\"file\"; filename=\"");
sb.Append(saveName);
sb.Append("\"\r\nContent-Type: ");
sb.Append("application/octet-stream");
sb.Append("\r\n\r\n");
string strPostHeader = sb.ToString();
byte[] postHeaderBytes = Encoding.UTF8.GetBytes(strPostHeader);
// 根据uri创建HttpWebRequest对象
HttpWebRequest httpReq = (HttpWebRequest)WebRequest.Create(new Uri(address));
httpReq.Method = "POST";
//对发送的数据不使用缓存
httpReq.AllowWriteStreamBuffering = false;
//设置获得响应的超时时间（300秒）
httpReq.Timeout = 300000;
httpReq.ContentType = "multipart/form-data; boundary=" + strBoundary;
long length = fs.Length + postHeaderBytes.Length + boundaryBytes.Length;
long fileLength = fs.Length;
httpReq.ContentLength = length;
try
{
progressBar.Properties.Maximum = int.MaxValue;
progressBar.Properties.Minimum = 0;
progressBar.EditValue = 0;
//每次上传4k
int bufferLength = 4096;
byte[] buffer = new byte[bufferLength];
//已上传的字节数
long offset = 0;
//开始上传时间
DateTime startTime = DateTime.Now;
int size = r.Read(buffer, 0, bufferLength);
using (Stream postStream = httpReq.GetRequestStream())
{
//发送请求头部消息
postStream.Write(postHeaderBytes, 0, postHeaderBytes.Length);
while (size > 0)
{
postStream.Write(buffer, 0, size);////文件的内容
offset += size;
progressBar.EditValue = (int)(offset * (int.MaxValue / length));
TimeSpan span = DateTime.Now - startTime;
double second = span.TotalSeconds;
lblTime.Text = "已用时：" + second.ToString("F2") + "秒";
if (second > 0.001)
{
lblSpeed.Text = " 平均速度：" + (offset / 1024 / second).ToString("0.00") + "KB/秒";
}
else
{
lblSpeed.Text = " 正在连接…";
}
lblState.Text = "已上传：" + (offset * 100.0 / length).ToString("F2") + "%";
lblSize.Text = (offset / 1048576.0).ToString("F2") + "M/" + (fileLength / 1048576.0).ToString("F2") + "M";
System.Windows.Forms.Application.DoEvents();
size = r.Read(buffer, 0, bufferLength);
}
//添加尾部的时间戳
postStream.Write(boundaryBytes, 0, boundaryBytes.Length);
}//postStream.Close();
//获取服务器端的响应
WebResponse webRespon = httpReq.GetResponse();
Stream s = webRespon.GetResponseStream();
StreamReader sr = new StreamReader(s);
//读取服务器端返回的消息
String sReturnString = sr.ReadLine();
s.Close();
sr.Close();
if (sReturnString == "Success")
{
returnValue = 1;
}
else if (sReturnString == "Error")
{
returnValue = 0;
}
}
catch
{
returnValue = 0;
}
finally
{
fs.Close();
r.Close();
}
return returnValue;
}
调用：
/// <summary>
/// HttpWebRequest上传
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void btnUpload_Click(object sender, EventArgs e)
{
try
{
string iniPath = DataConvert.ToString(btnOpenDialog.EditValue);
if (iniPath.Length == 0)
{
XtraMessageBox.Show("请选择要上传的文件！");
return;
}
panelJD.Visible = true;
string address = string.Format("{0}Save.aspx", Core.CoreOption.WsAddressErp);
int rst = UploadFile(address, iniPath, "dd.rar", progressBarControl1);
}
catch (Exception err)
{
XtraMessageBox.Show(err.Message);
}
}
aspx文件：
protected void Page_Load(object sender, EventArgs e)
{
// 在此处放置用户代码以初始化页面
try
{
if (Request.Files.Count > 0)
{
foreach (string f in Request.Files.AllKeys)
{
HttpPostedFile file = Request.Files[f];
string filePath = @"D:\Temp\" + file.FileName;
//string p= this.MapPath("test") + "//" + file.FileName;
file.SaveAs(filePath);
Response.Write("Success/r/n");
}
}
}
catch
{
Response.Write("Error/r/n");
}
}
同时需要配置WebConfig文件的httpRuntime 如下：
<httpRuntime maxRequestLength="102400" executionTimeout="300"/>
不能的话最大只能上传4M了。要是想上传更大的文件，maxRequestLength，executionTimeout设置大些，同时WinForm下的代码行
//设置获得响应的超时时间（300秒）
httpReq.Timeout = 300000;
也要修改，另外别忘了看看IIS的连接超时是否设置为足够大。
