C#如何自定义multipart/form-data的解析器

using System; using System.Collections.Generic; using System.IO; using System.Text; using System.Text.RegularExpressions; namespace YongFrame.Common.Utils { /// 
 /// multipart/form-data的解析器 /// 
 internal class HttpMultipartParser { /// 
 /// 参数集合 /// 
 public IDictionary Parameters = new Dictionary(); /// 
 /// 上传文件部分参数 /// 
 public string FilePartName { get; } /// 
 /// 是否解析成功 /// 
 public bool Success { get; private set; } /// 
 /// 请求类型 /// 
 public string ContentType { get; private set; } /// 
 /// 上传的文件名 /// 
 public string Filename { get; private set; } /// 
 /// 上传的文件内容 /// 
 public byte[] FileContents { get; private set; } /// 
 /// 解析multipart/form-data格式的文件请求，默认编码为utf8 /// 
 ///  ///  public HttpMultipartParser(Stream stream, string filePartName) { FilePartName = filePartName; Parse(stream, Encoding.UTF8); } /// 
 /// 解析multipart/form-data格式的字符串 /// 
 ///  public HttpMultipartParser(string content) { var array = Encoding.UTF8.GetBytes(content); var stream = new MemoryStream(array); Parse(stream, Encoding.UTF8); } /// 
 /// 解析multipart/form-data格式的文件请求 /// 
 ///  /// 编码 ///  public HttpMultipartParser(Stream stream, Encoding encoding, string filePartName) { FilePartName = filePartName; Parse(stream, encoding); } private void Parse(Stream stream, Encoding encoding) { Success = false; var data = ToByteArray(stream); var content = encoding.GetString(data); var delimiterEndIndex = content.IndexOf("\r\n", StringComparison.Ordinal); if (delimiterEndIndex > -1) { var delimiter = content.Substring(0, content.IndexOf("\r\n", StringComparison.Ordinal)).Trim(); var sections = content.Split(new[] {delimiter}, StringSplitOptions.RemoveEmptyEntries); foreach (var s in sections) { if (s.Contains("Content-Disposition")) { var nameMatch = new Regex(@"(?<=name\=\"")(.*?)(?=\"")").Match(s); var name = nameMatch.Value.Trim().ToLower(); if (name == FilePartName && !string.IsNullOrEmpty(FilePartName)) { var re = new Regex(@"(?<=Content\-Type:)(.*?)(?=\r\n\r\n)"); var contentTypeMatch = re.Match(content); re = new Regex(@"(?<=filename\=\"")(.*?)(?=\"")"); var filenameMatch = re.Match(content); if (contentTypeMatch.Success && filenameMatch.Success) { ContentType = contentTypeMatch.Value.Trim(); Filename = filenameMatch.Value.Trim(); var startIndex = contentTypeMatch.Index + contentTypeMatch.Length + "\r\n\r\n".Length; var delimiterBytes = encoding.GetBytes("\r\n" + delimiter); var endIndex = IndexOf(data, delimiterBytes, startIndex); var contentLength = endIndex - startIndex; var fileData = new byte[contentLength]; Buffer.BlockCopy(data, startIndex, fileData, 0, contentLength); FileContents = fileData; } } else if (!string.IsNullOrWhiteSpace(name)) { var startIndex = nameMatch.Index + nameMatch.Length + "\r\n\r\n".Length; Parameters.Add(name, s.Substring(startIndex).TrimEnd('\r', '\n').Trim()); } } } if (FileContents != null || Parameters.Count != 0) { Success = true; } } } public static int IndexOf(byte[] searchWithin, byte[] serachFor, int startIndex) { var index = 0; var startPos = Array.IndexOf(searchWithin, serachFor[0], startIndex); if (startPos != -1) { while (startPos + index 

 HttpMultipartParser parser = new HttpMultipartParser(paramData);             if (!parser.Success)             {                 result.Code = -1;                 result.Message = "请求数据格式不能正确";                 return result;             }             if (!parser.Parameters.ContainsKey("optid") || parser.Parameters["optid"] == null || string.IsNullOrEmpty(parser.Parameters["optid"]))             {                 result.Code = -1;                 result.Message = "用户名不能为空";                 return result;             }

public void Upload(Stream stream) {     HttpMultipartParser parser = new HttpMultipartParser(stream, "image");       if (parser.Success)     {         string user = HttpUtility.UrlDecode(parser.Parameters["user"]);         string title = HttpUtility.UrlDecode(parser.Parameters["title"]);           // Save the file somewhere         File.WriteAllBytes(FILE_PATH + title + FILE_EXT, parser.FileContents);     } }