diff --git a/.gitignore b/.gitignore
index 6975b91..9bac4aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,7 +7,7 @@
 ._*
 .idea
 .vscode
-.tmp
 
 
+.tmp/
 node_modules/
\ No newline at end of file
diff --git a/index.js b/index.js
index e5309bc..632edde 100644
--- a/index.js
+++ b/index.js
@@ -39,6 +39,8 @@ export default class Request {
   #req = null
   #res = null
 
+  #opts = {}
+
   #query = null
   #body = null
   #cookies = Object.create(null)
@@ -49,7 +51,7 @@ export default class Request {
   url = ''
   host = '127.0.0.1'
 
-  constructor(req, res) {
+  constructor(req, res, opts = {}) {
     this.method = req.method.toUpperCase()
 
     this.#req = req
@@ -58,6 +60,8 @@ export default class Request {
     this.host = req.headers['host']
     this.#cookies = parseCookie(this.headers['cookie'] || '')
 
+    Object.assign(this.#opts, opts)
+
     this.#init()
   }
 
@@ -114,7 +118,7 @@ export default class Request {
 
     contentType = this.header('content-type') || DEFAULT_FORM_TYPE
 
-    form = new Parser(this.#req, { uploadDir: tmpdir })
+    form = new Parser(this.#req, { ...this.#opts, uploadDir: tmpdir })
 
     form
       .on('field', (name, value) => {
diff --git a/lib/index.js b/lib/index.js
index 30a5812..a524bf4 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -16,6 +16,20 @@ function randomPath(uploadDir) {
   return join(uploadDir, name)
 }
 
+function parseFilename(headerValue) {
+  let matches = headerValue.match(/\bfilename="(.*?)"($|; )/i)
+  if (!matches) {
+    return
+  }
+
+  let filename = matches[1].slice(matches[1].lastIndexOf('\\') + 1)
+  filename = filename.replace(/%22/g, '"')
+  filename = filename.replace(/&#([\d]{4});/g, function (m, code) {
+    return String.fromCharCode(code)
+  })
+  return filename
+}
+
 /* ------------------------------------- */
 
 export default class IncomingForm extends EventEmitter {
@@ -31,7 +45,7 @@ export default class IncomingForm extends EventEmitter {
   bytesExpected = null
 
   #parser = null
-  #pending = true
+  #pending = 0
 
   #openedFiles = []
 
@@ -42,7 +56,6 @@ export default class IncomingForm extends EventEmitter {
 
     this.uploadDir = opts.uploadDir
     this.encoding = opts.encoding || 'utf-8'
-    this.multiples = opts.multiples || false
 
     // Parse headers and setup the parser, ready to start listening for data.
     this.writeHeaders(req.headers)
@@ -134,8 +147,8 @@ export default class IncomingForm extends EventEmitter {
       file.open()
 
       this.#openedFiles.push(file)
-
-      this.#pending = true
+      // 表单解析完的时候文件写入不一定完成了, 所以需要加入pending计数
+      this.#pending++
 
       part
         .on('data', buffer => {
@@ -145,12 +158,13 @@ export default class IncomingForm extends EventEmitter {
           file.write(buffer)
         })
         .on('end', () => {
-          console.log('file part end...')
+          if (part.ended) {
+            return
+          }
+          part.ended = true
           file.end(() => {
-            console.log('<><><><>', part.name, file)
             this.emit('file', part.name, file)
-            this.#pending = false
-            // this.#handleEnd()
+            this.#pending--
           })
         })
     }
@@ -199,118 +213,99 @@ export default class IncomingForm extends EventEmitter {
   }
 
   #createMultipartParser(boundary) {
-    let parser = new MultipartParser(boundary)
     let headerField, headerValue, part
 
-    parser
-      .on('partBegin', function () {
-        part = new Stream()
-        part.readable = true
-        part.headers = {}
-        part.name = null
-        part.filename = null
-        part.mime = null
+    this.#parser = new MultipartParser(boundary)
 
-        part.transferEncoding = 'binary'
-        part.transferBuffer = ''
+    this.#parser.$partBegin = function () {
+      part = new Stream()
+      part.readable = true
+      part.headers = {}
+      part.name = null
+      part.filename = null
+      part.mime = null
 
-        headerField = ''
-        headerValue = ''
-      })
-      .on('headerField', (b, start, end) => {
-        headerField += b.toString(this.encoding, start, end)
-      })
-      .on('headerValue', (b, start, end) => {
-        headerValue += b.toString(this.encoding, start, end)
-      })
-      .on('headerEnd', () => {
-        headerField = headerField.toLowerCase()
-        part.headers[headerField] = headerValue
+      part.transferEncoding = 'binary'
+      part.transferBuffer = ''
 
-        var m = headerValue.match(/\bname="([^"]+)"/i)
-        if (headerField == 'content-disposition') {
-          if (m) {
-            part.name = m[1]
+      headerField = ''
+      headerValue = ''
+    }
+
+    this.#parser.$headerField = b => {
+      headerField += b.toString(this.encoding)
+    }
+
+    this.#parser.$headerValue = b => {
+      headerValue += b.toString(this.encoding)
+    }
+
+    this.#parser.$headerEnd = () => {
+      headerField = headerField.toLowerCase()
+      part.headers[headerField] = headerValue
+
+      let matches = headerValue.match(/\bname="([^"]+)"/i)
+      if (headerField == 'content-disposition') {
+        if (matches) {
+          part.name = matches[1]
+        }
+
+        part.filename = parseFilename(headerValue)
+      } else if (headerField == 'content-type') {
+        part.mime = headerValue
+      } else if (headerField == 'content-transfer-encoding') {
+        part.transferEncoding = headerValue.toLowerCase()
+      }
+
+      headerField = ''
+      headerValue = ''
+    }
+
+    this.#parser.$headersEnd = () => {
+      switch (part.transferEncoding) {
+        case 'binary':
+        case '7bit':
+        case '8bit':
+          this.#parser.$partData = function (b) {
+            part.emit('data', b)
           }
+          this.#parser.$partEnd = function () {
+            part.emit('end')
+          }
+          break
 
-          part.filename = this._fileName(headerValue)
-        } else if (headerField == 'content-type') {
-          part.mime = headerValue
-        } else if (headerField == 'content-transfer-encoding') {
-          part.transferEncoding = headerValue.toLowerCase()
-        }
+        case 'base64':
+          this.#parser.$partData = function (b) {
+            part.transferBuffer += b.toString('ascii')
 
-        headerField = ''
-        headerValue = ''
-      })
-      .on('headersEnd', () => {
-        switch (part.transferEncoding) {
-          case 'binary':
-          case '7bit':
-          case '8bit':
-            parser
-              .on('partData', function (b, start, end) {
-                part.emit('data', b.slice(start, end))
-              })
-              .on('partEnd', function () {
-                part.emit('end')
-              })
-            break
+            // 确保offset的值能被4整除
+            let offset = ~~(part.transferBuffer.length / 4) * 4
+            part.emit(
+              'data',
+              Buffer.from(part.transferBuffer.slice(0, offset), 'base64')
+            )
+            part.transferBuffer = part.transferBuffer.slice(offset)
+          }
+          this.#parser.$partEnd = function () {
+            part.emit('data', Buffer.from(part.transferBuffer, 'base64'))
+            part.emit('end')
+          }
+          break
 
-          case 'base64':
-            parser
-              .on('partData', function (b, start, end) {
-                part.transferBuffer += b.slice(start, end).toString('ascii')
+        default:
+          return this.#handleError(new Error('unknown transfer-encoding'))
+      }
 
-                /*
-          four bytes (chars) in base64 converts to three bytes in binary
-          encoding. So we should always work with a number of bytes that
-          can be divided by 4, it will result in a number of buytes that
-          can be divided vy 3.
-          */
-                var offset = parseInt(part.transferBuffer.length / 4, 10) * 4
-                part.emit(
-                  'data',
-                  Buffer.from(
-                    part.transferBuffer.substring(0, offset),
-                    'base64'
-                  )
-                )
-                part.transferBuffer = part.transferBuffer.substring(offset)
-              })
-              .on('partEnd', function () {
-                part.emit('data', Buffer.from(part.transferBuffer, 'base64'))
-                part.emit('end')
-              })
-            break
+      this.#handlePart(part)
+    }
 
-          default:
-            return this.#handleError(new Error('unknown transfer-encoding'))
-        }
-
-        this.#handlePart(part)
-      })
-      .on('end', () => {
-        if (this.#pending) {
-          setTimeout(_ => parser.emit('end'))
-        } else {
-          this.#handleEnd()
-        }
-      })
-
-    this.#parser = parser
-  }
-
-  _fileName(headerValue) {
-    var m = headerValue.match(/\bfilename="(.*?)"($|; )/i)
-    if (!m) return
-
-    var filename = m[1].substr(m[1].lastIndexOf('\\') + 1)
-    filename = filename.replace(/%22/g, '"')
-    filename = filename.replace(/&#([\d]{4});/g, function (m, code) {
-      return String.fromCharCode(code)
-    })
-    return filename
+    this.#parser.$end = () => {
+      if (this.#pending > 0) {
+        setTimeout(_ => this.#parser.$end())
+      } else {
+        this.#handleEnd()
+      }
+    }
   }
 
   #createUrlencodedParser() {
diff --git a/lib/json_parser.js b/lib/json_parser.js
index 664f5e9..779a2ad 100644
--- a/lib/json_parser.js
+++ b/lib/json_parser.js
@@ -19,10 +19,10 @@ export class JSONParser extends EventEmitter {
       try {
         fields = JSON.parse(data)
       } catch (e) {
-        try{
+        try {
           // 非标准的json语法,尝试用 Function 解析
           fields = Function(`try{return ${data}}catch(e){}`)()
-        }catch(err){}
+        } catch (err) {}
       }
 
       this.emit('field', false, fields)
@@ -30,7 +30,14 @@ export class JSONParser extends EventEmitter {
 
       this.#buff = null
     } else {
-      this.emit('error', new Error(`The uploaded data is incomplete. Expected ${this.#byteLen}, Received ${this.#buff.length} .`))
+      this.emit(
+        'error',
+        new Error(
+          `The uploaded data is incomplete. Expected ${
+            this.#byteLen
+          }, Received ${this.#buff.length} .`
+        )
+      )
     }
   }
 }
diff --git a/lib/multipart_parser.js b/lib/multipart_parser.js
index cea3494..9909bbf 100644
--- a/lib/multipart_parser.js
+++ b/lib/multipart_parser.js
@@ -1,47 +1,49 @@
 import { EventEmitter } from 'node:events'
 
-var s = 0,
-  STATE_DICT = {
-    PARSER_UNINITIALIZED: s++,
-    START: s++,
-    START_BOUNDARY: s++,
-    HEADER_FIELD_START: s++,
-    HEADER_FIELD: s++,
-    HEADER_VALUE_START: s++,
-    HEADER_VALUE: s++,
-    HEADER_VALUE_ALMOST_DONE: s++,
-    HEADERS_ALMOST_DONE: s++,
-    PART_DATA_START: s++,
-    PART_DATA: s++,
-    PART_END: s++,
-    END: s++
-  },
-  f = 1,
-  F = {
-    PART_BOUNDARY: f,
-    LAST_BOUNDARY: (f *= 2)
-  },
-  LF = 10,
-  CR = 13,
-  SPACE = 32,
-  HYPHEN = 45,
-  COLON = 58,
-  A = 97,
-  Z = 122,
-  lower = function (c) {
-    return c | 0x20
-  }
+let s = 0
+const STATE_DICT = {
+  PARSER_UNINITIALIZED: s++,
+  START: s++,
+  START_BOUNDARY: s++,
+  HEADER_FIELD_START: s++,
+  HEADER_FIELD: s++,
+  HEADER_VALUE_START: s++,
+  HEADER_VALUE: s++,
+  HEADER_VALUE_ALMOST_DONE: s++,
+  HEADERS_ALMOST_DONE: s++,
+  PART_DATA_START: s++,
+  PART_DATA: s++,
+  PART_END: s++,
+  END: s++
+}
+let f = 1
+const FLAG_DICT = {
+  PART_BOUNDARY: f,
+  LAST_BOUNDARY: (f *= 2)
+}
 
-  function stateToString(stateNumber) {
-    for (let state in STATE_DICT) {
-      let number = STATE_DICT[state]
-      if (number === stateNumber) {
-        return state
-      }
+const LF = 10
+const CR = 13
+const SPACE = 32
+const HYPHEN = 45
+const COLON = 58
+const LETTER_A = 97
+const LETTER_Z = 122
+
+function lower(c) {
+  return c | 0x20
+}
+
+function stateToString(value) {
+  for (let key in STATE_DICT) {
+    let number = STATE_DICT[key]
+    if (number === value) {
+      return key
     }
   }
+}
 
-export class MultipartParser extends EventEmitter {
+export class MultipartParser {
   boundary = null
   boundaryChars = null
   lookbehind = null
@@ -50,11 +52,7 @@ export class MultipartParser extends EventEmitter {
   index = null
   flags = 0
 
-
-
   constructor(str) {
-    super()
-
     this.boundary = Buffer.alloc(str.length + 4)
     this.boundary.write('\r\n--', 0)
     this.boundary.write(str, 4)
@@ -67,8 +65,32 @@ export class MultipartParser extends EventEmitter {
     }
   }
 
+  #mark(k, v) {
+    this[k + 'Mark'] = v
+  }
+
+  #emit(name, buff, idx, cleanup) {
+    let mark = name + 'Mark'
+    if (this[mark] !== void 0) {
+      let start = this[mark]
+      let end = buff.length
+
+      if (cleanup) {
+        end = idx
+        delete this[mark]
+      } else {
+        this[mark] = 0
+      }
+
+      if (start === end) {
+        return
+      }
+      this['$' + name](buff.slice(start, end))
+    }
+  }
+
   write(buffer) {
-    var i = 0,
+    let idx = 0,
       len = buffer.length,
       prevIndex = this.index,
       index = this.index,
@@ -83,55 +105,37 @@ export class MultipartParser extends EventEmitter {
       c,
       cl
 
-      let mark =  (name) => {
-        this[name + 'Mark'] = i
-      },
-      dataCallback =  (name, clear) => {
-        var markSymbol = name + 'Mark'
-        if ((markSymbol in this)) {
-          if (clear) {
-            this.emit(name, buffer, this[markSymbol], i)
-            delete this[markSymbol]
-          } else {
-            this.emit(name, buffer, this[markSymbol], buffer.length)
-            this[markSymbol] = 0
-          }
-        }
+    for (idx = 0; idx < len; idx++) {
+      c = buffer[idx]
 
-      }
-
-    // console.log('???? ', state, 'len: ', len);
-    for (i = 0; i < len; i++) {
-      c = buffer[i]
       switch (state) {
         case STATE_DICT.PARSER_UNINITIALIZED:
-          return i
+          return
 
         case STATE_DICT.START:
           index = 0
           state = STATE_DICT.START_BOUNDARY
 
         case STATE_DICT.START_BOUNDARY:
-          // console.log('=====>>>', index, c, boundary);
           if (index == boundary.length - 2) {
             if (c == HYPHEN) {
-              flags |= F.LAST_BOUNDARY
+              flags |= FLAG_DICT.LAST_BOUNDARY
             } else if (c != CR) {
-              return i
+              return
             }
             index++
             break
           } else if (index - 1 == boundary.length - 2) {
-            if (flags & F.LAST_BOUNDARY && c == HYPHEN) {
-              this.emit('end')
+            if (flags & FLAG_DICT.LAST_BOUNDARY && c == HYPHEN) {
+              this.$end()
               state = STATE_DICT.END
               flags = 0
-            } else if (!(flags & F.LAST_BOUNDARY) && c == LF) {
+            } else if (!(flags & FLAG_DICT.LAST_BOUNDARY) && c == LF) {
               index = 0
-              this.emit('partBegin')
+              this.$partBegin()
               state = STATE_DICT.HEADER_FIELD_START
             } else {
-              return i
+              return
             }
             break
           }
@@ -143,10 +147,10 @@ export class MultipartParser extends EventEmitter {
             index++
           }
           break
-        
+
         case STATE_DICT.HEADER_FIELD_START:
           state = STATE_DICT.HEADER_FIELD
-          mark('headerField')
+          this.#mark('headerField', idx)
           index = 0
 
         case STATE_DICT.HEADER_FIELD:
@@ -164,72 +168,72 @@ export class MultipartParser extends EventEmitter {
           if (c == COLON) {
             if (index == 1) {
               // empty header field
-              return i
+              return
             }
-            dataCallback('headerField', true)
+            this.#emit('headerField', buffer, idx, true)
             state = STATE_DICT.HEADER_VALUE_START
             break
           }
 
           cl = lower(c)
-          if (cl < A || cl > Z) {
-            return i
+          if (cl < LETTER_A || cl > LETTER_Z) {
+            return
           }
           break
-        
+
         case STATE_DICT.HEADER_VALUE_START:
           if (c == SPACE) {
             break
           }
 
-          mark('headerValue')
+          this.#mark('headerValue', idx)
           state = STATE_DICT.HEADER_VALUE
-        
+
         case STATE_DICT.HEADER_VALUE:
           if (c == CR) {
-            dataCallback('headerValue', true)
-            this.emit('headerEnd')
+            this.#emit('headerValue', buffer, idx, true)
+            this.$headerEnd()
             state = STATE_DICT.HEADER_VALUE_ALMOST_DONE
           }
           break
 
         case STATE_DICT.HEADER_VALUE_ALMOST_DONE:
           if (c != LF) {
-            return i
+            return
           }
           state = STATE_DICT.HEADER_FIELD_START
           break
 
         case STATE_DICT.HEADERS_ALMOST_DONE:
           if (c != LF) {
-            return i
+            return
           }
 
-          this.emit('headersEnd')
+          this.$headersEnd()
           state = STATE_DICT.PART_DATA_START
           break
 
         case STATE_DICT.PART_DATA_START:
           state = STATE_DICT.PART_DATA
-          mark('partData')
+          this.#mark('partData', idx)
 
         case STATE_DICT.PART_DATA:
           prevIndex = index
 
           if (index === 0) {
             // boyer-moore derrived algorithm to safely skip non-boundary data
-            i += boundaryEnd
-            while (i < bufferLength && !(buffer[i] in boundaryChars)) {
-              i += boundaryLength
+            idx += boundaryEnd
+            while (idx < bufferLength && !(buffer[idx] in boundaryChars)) {
+              idx += boundaryLength
             }
-            i -= boundaryEnd
-            c = buffer[i]
+            idx -= boundaryEnd
+            c = buffer[idx]
           }
 
           if (index < boundary.length) {
             if (boundary[index] == c) {
               if (index === 0) {
-                dataCallback('partData', true)
+                this.#emit('partData', buffer, idx, true)
               }
               index++
             } else {
@@ -239,28 +243,28 @@ export class MultipartParser extends EventEmitter {
             index++
             if (c == CR) {
               // CR = part boundary
-              flags |= F.PART_BOUNDARY
+              flags |= FLAG_DICT.PART_BOUNDARY
             } else if (c == HYPHEN) {
               // HYPHEN = end boundary
-              flags |= F.LAST_BOUNDARY
+              flags |= FLAG_DICT.LAST_BOUNDARY
             } else {
               index = 0
             }
           } else if (index - 1 == boundary.length) {
-            if (flags & F.PART_BOUNDARY) {
+            if (flags & FLAG_DICT.PART_BOUNDARY) {
               index = 0
               if (c == LF) {
                 // unset the PART_BOUNDARY flag
-                flags &= ~F.PART_BOUNDARY
-                this.emit('partEnd')
-                this.emit('partBegin')
+                flags &= ~FLAG_DICT.PART_BOUNDARY
+                this.$partEnd()
+                this.$partBegin()
                 state = STATE_DICT.HEADER_FIELD_START
                 break
               }
-            } else if (flags & F.LAST_BOUNDARY) {
+            } else if (flags & FLAG_DICT.LAST_BOUNDARY) {
               if (c == HYPHEN) {
-                this.emit('partEnd')
-                this.emit('end')
+                this.$partEnd()
+                this.$end()
                 state = STATE_DICT.END
                 flags = 0
               } else {
@@ -278,43 +282,42 @@ export class MultipartParser extends EventEmitter {
           } else if (prevIndex > 0) {
             // if our boundary turned out to be rubbish, the captured lookbehind
             // belongs to partData
-            this.emit('partData', lookbehind, 0, prevIndex)
+
+            this.$partData(lookbehind.slice(0, prevIndex))
             prevIndex = 0
-            mark('partData')
+            this.#mark('partData', idx)
 
             // reconsider the current character even so it interrupted the sequence
             // it could be the beginning of a new sequence
-            i--
+            idx--
           }
 
           break
-        
+
         case STATE_DICT.END:
           break
 
         default:
-          return i
+          return
       }
     }
 
-    dataCallback('headerField')
-    dataCallback('headerValue')
-    dataCallback('partData')
+    this.#emit('headerField', buffer, idx)
+    this.#emit('headerValue', buffer, idx)
+    this.#emit('partData', buffer, idx)
 
     this.index = index
     this.state = state
     this.flags = flags
-
-  
   }
 
   end() {
-
     if (
       (this.state === STATE_DICT.HEADER_FIELD_START && this.index === 0) ||
-      (this.state === STATE_DICT.PART_DATA && this.index == this.boundary.length)
+      (this.state === STATE_DICT.PART_DATA &&
+        this.index == this.boundary.length)
     ) {
-      this.emit('end')
+      this.$end()
     } else if (this.state !== STATE_DICT.END) {
       return new Error(
         'MultipartParser.end(): stream ended unexpectedly: ' + this.explain()
diff --git a/lib/urlencoded_parser.js b/lib/urlencoded_parser.js
index 1da0c39..78c61d0 100644
--- a/lib/urlencoded_parser.js
+++ b/lib/urlencoded_parser.js
@@ -17,11 +17,10 @@ export class UrlencodedParser extends EventEmitter {
   end() {
     let data = this.#buff.toString()
     let fields = parse(data)
-    
+
     this.#buff = null
-    
+
     this.emit('field', fields)
     this.emit('end')
-
   }
 }