C# 模擬上傳圖片

上傳圖片的格式必定要按規定的寫，否則沒辦法正確上傳的。

我在上傳的時候就是值前面沒有空一行，致使上傳不成功，很糾結的錯誤。

我要模擬的是一個FLASH的上傳控件，我開始用HttpAnalyze抓包是抓不到的。後來上網搜索到了【抓包工具】Charles v3.6.4，下載安裝後，能夠抓到FLASH上傳時候的包了。

FLASH上傳應該也是POST，可能不是HTTP包，但應該能夠按HTTP的方式發送吧。結果證實個人想法是對的，能夠正常上傳。

FLASH上傳與普通的按鈕上傳控件有什麼區別呢？有待搜索到相關資料。

Charles v3.6.4 下載地址

原版下載地址:   http://www.charlesproxy.com/download/ 
破解補丁下載地址:   http://note.sdo.com/u/1528563206/n/r70o6~jK35opnM10I000fd

下面是參考代碼，注意上傳的格式就好。

using System;  
using System.Collections.Generic;  
using System.Linq;  
using System.Text;  
using System.Net;  
using System.IO;  
namespace ConsoleApplication1  
{  
    class Program  
    {  
        static void Main(string[] args)  
        {  
            Dictionary<string, string> inputDic=new Dictionary<string,string>();  
            inputDic.Add("username","westfruit");  
            inputDic.Add("password","123456");  
            PostFile("http://avatar.csdn.net/0/1/1/1_zfrong.jpg", "http://www.westfruit.com/news/uppic.asp?strAction=shangchuan", @"D:\1.jpg", "application/octet-stream", inputDic);  
        }  
 
        #region 下載文件並上傳到指定頁面  
        /** 
         * 若是要在客戶端向服務器上傳文件，咱們就必須模擬一個POST multipart/form-data類型的請求 
         * Content-Type必須是multipart/form-data。 
         * 以multipart/form-data編碼的POST請求格式與application/x-www-form-urlencoded徹底不一樣 
         * multipart/form-data須要首先在HTTP請求頭設置一個分隔符,例如7d4a6d158c9： 
         * 咱們模擬的提交要設定 content-type不一樣於非含附件的post時候的content-type 
         * 這裏須要： ("Content-Type", "multipart/form-data; boundary=ABCD"); 
         * 而後，將每一個字段用「--7d4a6d158c9」分隔，最後一個「--7d4a6d158c9--」表示結束。 
         * 例如，要上傳一個title字段"Today"和一個文件C:\1.txt，HTTP正文以下： 
         *  
         * --7d4a6d158c9 
         * Content-Disposition: form-data; name="title" 
         * \r\n\r\n 
         * Today 
         * --7d4a6d158c9 
         * Content-Disposition: form-data; name="1.txt"; filename="C:\1.txt" 
         * Content-Type: text/plain 
         * 若是是圖片Content-Type: application/octet-stream 
         * \r\n\r\n 
         * <這裏是1.txt文件的內容> 
         * --7d4a6d158c9 
         * \r\n 
         * 請注意，每一行都必須以\r\n結束value前面必須有2個\r\n，包括最後一行。 
        */  
        /// <summary>  
        /// 下載文件上傳到指定地址  
        /// </summary>  
        /// <param name="getUrl">文件下載地址</param>  
        /// <param name="postUrl">文件上傳地址</param>  
        /// <param name="fileName">file控件名稱</param>  
        /// <param name="fileType">上傳文件類型</param>  
        /// <param name="inputParamter">其餘表單元素</param>  
        public static void PostFile(string getUrl, string postUrl, string fileName, string fileType, Dictionary<string, string> inputDic)  
        {  
            
            CredentialCache cache = new CredentialCache();//建立緩存容器  
            cache.Add(new Uri("http://www.westfruit.com/"), "Basic", new NetworkCredential("westfruit", "7766517"));  
            CookieContainer cookies = new CookieContainer();//建立cookie容器  
            MemoryStream fileStream = GetFileStream(getUrl);//下載文件返回內存流  
            // cast the WebRequest to a HttpWebRequest since we're using HTTPS   
            string boundary = "----------" + DateTime.Now.Ticks.ToString("x");//元素分割標記  
            HttpWebRequest httpWebRequest2 = (HttpWebRequest)WebRequest.Create(postUrl);  
            httpWebRequest2.Credentials = cache;  
            httpWebRequest2.CookieContainer = cookies;  
            httpWebRequest2.ContentType = "multipart/form-data; boundary=" + boundary;//其餘地方的boundary要比這裏多--  
            httpWebRequest2.Method = "POST";//Post請求方式  
            // Build up the post message 拼接建立表單內容   
            StringBuilder sb = new StringBuilder();  
            //拼接非文件表單控件  
            //遍歷字典取出表單普通空間的健和值  
            foreach (KeyValuePair<string, string> dicItem in inputDic)  
            {  
                sb.Append("--" + boundary);  
                sb.Append("\r\n");  
                sb.Append("Content-Disposition: form-data; name=\"" + dicItem.Key + "\"");  
                sb.Append("\r\n");  
                sb.Append("\r\n");  
                sb.Append(dicItem.Value);//value前面必須有2個換行  
                sb.Append("\r\n");  
            }  
            //拼接文件控件  
            sb.Append("--"+boundary);  
            sb.Append("\r\n");  
            sb.Append("Content-Disposition: form-data; name=\"file1\"; filename=\"C:\\upload" + Path.GetFileName(fileName) + "\"");  
            sb.Append("\r\n");  
            sb.Append("Content-Type: application/octet-stream");  
            sb.Append("\r\n");  
            sb.Append("\r\n");//value前面必須有2個換行  
            byte[] postHeaderBytes = Encoding.UTF8.GetBytes(sb.ToString());  
            // Build the trailing boundary string as a byte array 建立結束標記  
            // ensuring the boundary appears on a line by itself   
            byte[] boundaryBytes = Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");  
            //http請求總長度  
            httpWebRequest2.ContentLength = postHeaderBytes.Length + fileStream.Length + boundaryBytes.Length;  
            Stream requestStream = httpWebRequest2.GetRequestStream(); //定義一個http請求流  
            // Write out our post header 將開始標記寫入流  
            requestStream.Write(postHeaderBytes, 0, postHeaderBytes.Length);  
            // Write out the file contents 將附件寫入流,最大4M  
            byte[] buffer = new Byte[checked((uint)Math.Min(4096, (int)fileStream.Length))];  
            int bytesRead = 0;  
            while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)  
                requestStream.Write(buffer, 0, bytesRead);  
            fileStream.Dispose();  
            // Write out the trailing boundary 將結束標記寫入流  
            requestStream.Write(boundaryBytes, 0, boundaryBytes.Length);  
            //Send http request back WebResponse 發送http請求  
            WebResponse webResponse2 = httpWebRequest2.GetResponse();  
            //從WebResponse中解析出html代碼開始  
            Stream htmlStream = webResponse2.GetResponseStream();  
            string HTML = GetHtml(htmlStream, "UTF-8");  
            htmlStream.Dispose();  
            //從WebResponse中解析出html代碼結束  
        }  
        #endregion  
        #region 下載文件  
        /// <summary>  
        /// 從互聯網下載文件  
        /// </summary>  
        /// <param name="getUrl">文件地址</param>  
        /// <returns>內存流</returns>  
        public static MemoryStream GetFileStream(string getUrl)  
        {  
            MemoryStream fileStream;//定義一個內存流保存接收到的文件流  
            HttpWebRequest httpWebRequest1 = (HttpWebRequest)WebRequest.Create(getUrl);  
            WebResponse webResponse1 = httpWebRequest1.GetResponse();  
            byte[] buffer1 = new byte[4096];//定義一個4M大小的數字  
            Stream stream1 = webResponse1.GetResponseStream();//定義一個流接受html返回的文件流  
            fileStream = new MemoryStream();//stream1不支持查找操做因此將其轉入內存流  
            int l;  
            do  
            {  
                l = stream1.Read(buffer1, 0, buffer1.Length);  
                if (l > 0)  
                {  
                    fileStream.Write(buffer1, 0, l);//將文件流按字節寫入內存流  
                }  
            }  
            while (l > 0);  
            stream1.Close();  
            fileStream.Position = 0;  
            return fileStream;  
        }  
        #endregion  
        #region 解析html代碼  
        /// <summary>  
        /// 從html流中解析出html代碼  
        /// </summary>  
        /// <param name="htmlStream">html流</param>  
        /// <param name="Encoding">編碼格式</param>  
        /// <returns>html</returns>  
        public static string GetHtml(Stream htmlStream, string Encoding)  
        {  
            StreamReader objReader = new StreamReader(htmlStream, System.Text.Encoding.GetEncoding(Encoding));  
            string HTML = "";  
            string sLine = "";  
            int i = 0;  
            while (sLine != null)  
            {  
                i++;  
                sLine = objReader.ReadLine();  
                if (sLine != null)  
                    HTML += sLine;  
            }  
            HTML = HTML.Replace("<", "<");  
            HTML = HTML.Replace(">", ">");  
            objReader.Dispose();  
            return HTML;  
        }  
        #endregion  
    }  
}