学步园

假如某网站有个表单，例如(url: http: // localhost/login.aspx)：
帐号  
密码  

我们需要在程序中提交数据到这个表单，对于这种表单，我们可以使用 WebClient.UploadData 方法来实现，将所要上传的数据拼成字符即可，程序很简单：

string  uriString  =   " http://localhost/login.aspx " ;
//  创建一个新的 WebClient 实例.
WebClient myWebClient  =   new  WebClient();
string  postData  =   " Username=admin&Password=admin " ;
//  注意这种拼字符串的ContentType
myWebClient.Headers.Add( " Content-Type " , " application/x-www-form-urlencoded " );
//  转化成二进制数组
byte [] byteArray  =  Encoding.ASCII.GetBytes(postData);
//  上传数据，并获取返回的二进制数据.
byte [] responseArray  =  myWebClient.UploadData(uriString, " POST " ,byteArray);


对于文件上传类的表单，例如(url: http: // localhost/uploadFile.aspx)：
文件  

对于这种表单，我们可以使用
String uriString  =   " http://localhost/uploadFile.aspx " ;

//  创建一个新的 WebClient 实例.
WebClient myWebClient  =   new  WebClient();

string  fileName  =   @" C:/upload.txt " ;

//  直接上传，并获取返回的二进制数据.
byte [] responseArray  =  myWebClient.UploadFile(uriString, " POST " ,fileName);


还有一种表单，不仅有文字，还有文件，例如(url: http: // localhost/uploadData.aspx)：
文件名  
文件  

对于这种表单，似乎前面的两种方法都不能适用，对于第一种方法，不能直接拼字符串，对于第二种，我们只能传文件，重新回到第一个方法，注意参数：
public   byte [] UploadData(
    string  address,
    string  method,
    byte [] data
);
在第一个例子中，是通过拼字符串来得到byte[] data参数值的，对于这种表单显然不行，反过来想想，对于 uploadData.aspx这样的程序来说，直接通过网页提交数据，后台所获取到的流是什么样的呢？（在我以前的一篇blog中，曾分析过这个问题：asp无组件上传进度条解决方案），最终的数据如下：

----------------------------- 7d429871607fe
Content - Disposition: form - data; name = " file1 " ; filename = " G:/homepage.txt "
Content - Type: text / plain
宝玉：http: // www.webuc.net
----------------------------- 7d429871607fe
Content - Disposition: form - data; name = " filename "
default  filename
----------------------------- 7d429871607fe --


所以只要拼一个这样的byte[] data数据Post过去，就可以达到同样的效果了。但是一定要注意，对于这种带有文件上传的，其ContentType是不一样的，例如上面的这种，其ContentType为 " multipart/form-data; boundary=---------------------------7d429871607fe " 。有了ContentType，我们就可以知道boundary(就是上面的 " ---------------------------7d429871607fe " )，知道boundary了我们就可以构造出我们所需要的byte[] data了，最后，不要忘记，把我们构造的ContentType传到 WebClient中（例如:webClient.Headers.Add( " Content-Type " , ContentType);）这样，就可以通过WebClient.UploadData 方法上载文件数据了。

具体代码如下：
using  System;
using  System.Web;
using  System.IO;
using  System.Net;
using  System.Text;
using  System.Collections;

namespace  UploadData.Common
... {
       public class CreateBytes
    {
        Encoding encoding = Encoding.UTF8;
        public byte[] JoinBytes(ArrayList byteArrays)
        {
            int length = 0;
            int readLength = 0;
            // 加上结束边界
            string endBoundary = Boundary + "-- ";
            byte[] endBoundaryBytes = encoding.GetBytes(endBoundary);
            byteArrays.Add(endBoundaryBytes);

            foreach (byte[] b in byteArrays)
            {
                length += b.Length;
            }
            byte[] bytes = new byte[length];

            // 遍历复制
            foreach (byte[] b in byteArrays)
            {
                b.CopyTo(bytes, readLength);
                readLength += b.Length;
            }

            return bytes;
        }

           public bool UploadData(string uploadUrl, byte[] bytes, out byte[] responseBytes)
        {
            WebClient webClient = new WebClient();
            webClient.Headers.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
            webClient.Headers.Add("Accept-Language", "en-us,en;q=0.5");
            webClient.Headers.Add("Accept-Encoding", "gzip,deflate");
            webClient.Headers.Add("Accept-Charset", "ISO-8859-1,utf-8;q=0.7,*;q=0.7");
 
            //webClient.Headers.Add("Cookie", GetSessionID());
            webClient.Headers.Add("Content-Type", ContentType);

            try
            {
                responseBytes = webClient.UploadData(uploadUrl, bytes);
                return true;
            }
            catch (WebException ex)
            {
                Stream resp = ex.Response.GetResponseStream();
                responseBytes = new byte[ex.Response.ContentLength];
                resp.Read(responseBytes, 0, responseBytes.Length);
            }
            return false;
        }

        /**/
        /// 获取普通表单区域二进制数组
        public byte[] CreateFieldData(string fieldName, string fieldValue)
        {
            string textTemplate = Boundary + "/r/nContent-Disposition: form-data; {0}= /"{1}/" /r/n";
            //string textTemplate = Boundary + " Content-Disposition: form-data; {0}= /"{1}/" ";
            string text = String.Format(textTemplate, fieldName, fieldValue);
            byte[] bytes = encoding.GetBytes(text);
            return bytes;
        }

        public byte[] CreateFieldData(string fieldName, string filename, string contentType, byte[] fileBytes)
        {
            string end = " ";
            string textTemplate = Boundary + "/r/nContent-Disposition: form-data; name=/"{0}/"; filename=/"{1}/"/r/nContent-Type: {2} /r/n/r/n";
            //string textTemplate = Boundary + "Content-Disposition: form-data; name=/"{0}/"; filename=/"{1}/"  Content-Type: {2}";

            // 头数据
            string data = String.Format(textTemplate, fieldName, filename, contentType);
            byte[] bytes = encoding.GetBytes(data);

            // 尾数据
            byte[] endBytes = encoding.GetBytes(end);

            // 合成后的数组
            byte[] fieldData = new byte[bytes.Length + fileBytes.Length + endBytes.Length];
            // byte[] fieldData = new byte[bytes.Length + fileBytes.Length];
            bytes.CopyTo(fieldData, 0); // 头数据
            fileBytes.CopyTo(fieldData, bytes.Length); // 文件的二进制数据
            endBytes.CopyTo(fieldData, bytes.Length + fileBytes.Length); //

            return fieldData;
        }

        public string Boundary
        {
            get
            {
                string[] bArray, ctArray;
                string contentType = ContentType;
                ctArray = contentType.Split(';');
                if (ctArray[0].Trim().ToLower() == "multipart/form-data")
                {
                    bArray = ctArray[1].Split('=');
                    return "--" + bArray[1];
                }
                return null;
            }
        }

        public string ContentType
        {
            get
            {
                if (HttpContext.Current == null)
                {
                    return "multipart/form-data; boundary=-----------------------------7d5b915500cee";
                }
                return HttpContext.Current.Request.ContentType;
            }
        }
    }

 public class frmUpload : System.Windows.Forms.Form
    {
        private System.Windows.Forms.Label lblAmigoToken;
        private System.Windows.Forms.TextBox txtAmigoToken;
        private System.Windows.Forms.Label lblFilename;
        private System.Windows.Forms.TextBox txtFilename;
        private System.Windows.Forms.Button btnBrowse;
        private System.Windows.Forms.TextBox txtFileData;
        private System.Windows.Forms.Label lblFileData;
        private System.Windows.Forms.Button btnUpload;
        private System.Windows.Forms.OpenFileDialog openFileDialog1;
        private System.Windows.Forms.TextBox txtResponse;

        private System.ComponentModel.Container components = null;

        public frmUpload()
        {
            InitializeComponent();
        }

        protected override void Dispose(bool disposing)
       {
            if (disposing)
            {
                if (components != null)
               {
                    components.Dispose();
                }
            }
            base.Dispose(disposing);
        }

        private void InitializeComponent()
        {
            this.lblAmigoToken = new System.Windows.Forms.Label();
            this.txtAmigoToken = new System.Windows.Forms.TextBox();
            this.lblFilename = new System.Windows.Forms.Label();
            this.txtFilename = new System.Windows.Forms.TextBox();
            this.btnBrowse = new System.Windows.Forms.Button();
            this.txtFileData = new System.Windows.Forms.TextBox();
            this.lblFileData = new System.Windows.Forms.Label();
            this.btnUpload = new System.Windows.Forms.Button();
            this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
            this.txtResponse = new System.Windows.Forms.TextBox();
            this.SuspendLayout();
            //
            // lblAmigoToken
            //
            this.lblAmigoToken.Location = new System.Drawing.Point(40, 48);
            this.lblAmigoToken.Name = "lblAmigoToken";
            this.lblAmigoToken.Size = new System.Drawing.Size(72, 23);
            this.lblAmigoToken.TabIndex = 0;
            this.lblAmigoToken.Text = "AmigoToken";
            //
            // txtAmigoToken
            //
            this.txtAmigoToken.Location = new System.Drawing.Point(120, 48);
            this.txtAmigoToken.Name = "txtAmigoToken";
            this.txtAmigoToken.Size = new System.Drawing.Size(248, 21);
            this.txtAmigoToken.TabIndex = 1;
            this.txtAmigoToken.Text = "";
            //
            // lblFilename
            //
            this.lblFilename.Location = new System.Drawing.Point(40, 96);
            this.lblFilename.Name = "lblFilename";
            this.lblFilename.Size = new System.Drawing.Size(80, 23);
            this.lblFilename.TabIndex = 2;
            this.lblFilename.Text = "Filename";
            //
            // txtFilename
            //
            this.txtFilename.Location = new System.Drawing.Point(120, 96);
            this.txtFilename.Name = "txtFilename";
            this.txtFilename.Size = new System.Drawing.Size(248, 21);
            this.txtFilename.TabIndex = 3;
            this.txtFilename.Text = "";
            //
            // btnBrowse
            //
            this.btnBrowse.Location = new System.Drawing.Point(296, 144);
            this.btnBrowse.Name = "btnBrowse";
            this.btnBrowse.TabIndex = 4;
            this.btnBrowse.Text = "浏览";
            this.btnBrowse.Click += new System.EventHandler(this.btnBrowse_Click);
            //
            // txtFileData
            //
            this.txtFileData.Location = new System.Drawing.Point(120, 144);
            this.txtFileData.Name = "txtFileData";
            this.txtFileData.Size = new System.Drawing.Size(168, 21);
            this.txtFileData.TabIndex = 5;
            this.txtFileData.Text = "";
            //
            // lblFileData
            //
            this.lblFileData.Location = new System.Drawing.Point(40, 144);
            this.lblFileData.Name = "lblFileData";
            this.lblFileData.Size = new System.Drawing.Size(72, 23);
            this.lblFileData.TabIndex = 6;
            this.lblFileData.Text = "FileData";
            //
            // btnUpload
            //
            this.btnUpload.Location = new System.Drawing.Point(48, 184);
            this.btnUpload.Name = "btnUpload";
            this.btnUpload.TabIndex = 7;
            this.btnUpload.Text = "Upload";
            this.btnUpload.Click += new System.EventHandler(this.btnUpload_Click);
            //
            // txtResponse
            //
            this.txtResponse.Location = new System.Drawing.Point(136, 184);
            this.txtResponse.Multiline = true;
            this.txtResponse.Name = "txtResponse";
            this.txtResponse.Size = new System.Drawing.Size(248, 72);
            this.txtResponse.TabIndex = 8;
            this.txtResponse.Text = "";
            //
            // frmUpload
            //
            this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
            this.ClientSize = new System.Drawing.Size(400, 269);
            this.Controls.Add(this.txtResponse);
            this.Controls.Add(this.btnUpload);
            this.Controls.Add(this.lblFileData);
            this.Controls.Add(this.txtFileData);
            this.Controls.Add(this.btnBrowse);
            this.Controls.Add(this.txtFilename);
            this.Controls.Add(this.lblFilename);
            this.Controls.Add(this.txtAmigoToken);
            this.Controls.Add(this.lblAmigoToken);
            this.Name = "frmUpload";
            this.Text = "frmUpload";
            this.ResumeLayout(false);

        }

        [STAThread]
        static void Main()
        {
            Application.Run(new frmUpload());
        }

        private void btnUpload_Click(object sender, System.EventArgs e)
        {
            // 非空检验
            if (txtAmigoToken.Text.Trim() == "" || txtFilename.Text == "" || txtFileData.Text.Trim() == "")
            {
                MessageBox.Show("Please fill data");
                return;
            }

            // 所要上传的文件路径
            string path = txtFileData.Text.Trim();

            // 检查文件是否存在
            if (!File.Exists(path))
            {
                MessageBox.Show("{0} does not exist!", path);
                return;
            }

            // 读文件流
            FileStream fs = new FileStream(path, FileMode.Open,
                FileAccess.Read, FileShare.Read);

            // 这部分需要完善
            string ContentType = "application/octet-stream";
            byte[] fileBytes = new byte[fs.Length];
            fs.Read(fileBytes, 0, Convert.ToInt32(fs.Length));

            // 生成需要上传的二进制数组
            CreateBytes cb = new CreateBytes();
            // 所有表单数据
            ArrayList bytesArray = new ArrayList();
            // 普通表单
            bytesArray.Add(cb.CreateFieldData("FileName", txtFilename.Text));
            bytesArray.Add(cb.CreateFieldData("AmigoToken", txtAmigoToken.Text));
            // 文件表单
            bytesArray.Add(cb.CreateFieldData("FileData", path
                                                , ContentType, fileBytes));

            // 合成所有表单并生成二进制数组
            byte[] bytes = cb.JoinBytes(bytesArray);

            // 返回的内容
            byte[] responseBytes;

            // 上传到指定Url
            bool uploaded = cb.UploadData("http://localhost/UploadData/UploadAvatar.aspx", bytes, out responseBytes);

            // 将返回的内容输出到文件
            using (FileStream file = new FileStream(@"c: esponse.text", FileMode.Create, FileAccess.Write, FileShare.Read))
            {
                file.Write(responseBytes, 0, responseBytes.Length);
            }

            txtResponse.Text = System.Text.Encoding.UTF8.GetString(responseBytes);

        }

        private void btnBrowse_Click(object sender, System.EventArgs e)
        {
            if (openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                txtFileData.Text = openFileDialog1.FileName;
            }

        }
    }
}

使用实例

           string ContentType = "audio/wav";
                    CreateBytes cb = new CreateBytes();
                    //所有表单数据
                    ArrayList bytesArray = new ArrayList();
                    //文件表单
                    string filePath = ConfigurationManager.AppSettings["filePath"] + filename;
                    bytesArray.Add(cb.CreateFieldData("ringfile", filename, ContentType, GetFileBytes(filePath)));
                    //普通表单
                    bytesArray.Add(cb.encoding.GetBytes("/r/n"));
                    bytesArray.Add(cb.CreateFieldData("name", "model.auditiontype"));
                    bytesArray.Add(cb.encoding.GetBytes("/r/n"));
                    bytesArray.Add(cb.encoding.GetBytes("0"));
                    bytesArray.Add(cb.encoding.GetBytes("/r/n"));
                    bytesArray.Add(cb.CreateFieldData("name", "1"));
                    bytesArray.Add(cb.encoding.GetBytes("/r/n"));
                    bytesArray.Add(cb.encoding.GetBytes("1"));
                    bytesArray.Add(cb.encoding.GetBytes("/r/n"));
                    bytesArray.Add(cb.encoding.GetBytes("--"));

                    //合成所有表单并生成二进制数组
                    byte[] bytes = cb.JoinBytes(bytesArray);
                    //返回的内容
                    byte[] responseBytes;
                    //上传到指定Url
                   // Log(bytes);
                    bool uploaded = cb.UploadData(@"http://61.138.203.62:8080/systemportal/ring/basic/ringfile_update_submit.action", bytes, out responseBytes);

来至http://blog.csdn.net/Comman1999/archive/2007/11/21/1896302.aspx