PHP⼤⽂件分割分⽚上传实现代码服务端为什么不能直接传⼤⽂件？跟php.ini⾥⾯的⼏个配置有关upload_max_filesize = 2M //PHP最⼤能接受的⽂件⼤⼩post_max_size = 8M //PHP能收到的最⼤POST值'memory_limit = 128M //内存上限max_execution_time = 30 //最⼤执⾏时间当然不能简单粗暴的把上⾯⼏个值调⼤，否则服务器内存资源吃光是迟早的问题。
解决思路好在HTML5开放了新的FILE API，也可以直接操作⼆进制对象，我们可以直接在浏览器端实现⽂件切割，按照以前的做法就得⽤Flash的⽅案，实现起来会⿇烦很多。
JS思路1.监听上传按钮的onchange事件2.获取⽂件的FILE对象3.把⽂件的FILE对象进⾏切割，并且附加到FORMDATA对象中4.把FORMDATA对象通过AJAX发送到服务器5.重复3、4步骤，直到⽂件发送完。
PHP思路1.建⽴上传⽂件夹2.把⽂件从上传临时⽬录移动到上传⽂件夹3.所有的⽂件块上传完成后，进⾏⽂件合成4.删除⽂件夹5.返回上传后的⽂件路径DEMO代码前端部分代码<!doctype html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport"content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>Document</title><style>#progress{width: 300px;height: 20px;background-color:#f7f7f7;box-shadow:inset 0 1px 2px rgba(0,0,0,0.1);border-radius:4px;background-image:linear-gradient(to bottom,#f5f5f5,#f9f9f9);}#finish{background-color: #149bdf;background-image:linear-gradient(45deg,rgba(255,255,255,0.15) 25%,transparent 25%,transparent 50%,rgba(255,255,255,0.15) 50%,rgba(255,255,255,0.15) 75%,transparent 75%,transparent); background-size:40px 40px;height: 100%;}form{margin-top: 50px;}</style></head><body><div id="progress"><div id="finish" style="width: 0%;" progress="0"></div></div><form action="./upload.php"><input type="file" name="file" id="file"><input type="button" value="停⽌" id="stop"></form><script>var fileForm = document.getElementById("file");var stopBtn = document.getElementById('stop');var upload = new Upload();fileForm.onchange = function(){upload.addFileAndSend(this);}stopBtn.onclick = function(){this.value = "停⽌中";upload.stop();this.value = "已停⽌";}function Upload(){var xhr = new XMLHttpRequest();var form_data = new FormData();const LENGTH = 1024 * 1024;var start = 0;var end = start + LENGTH;var blob;var blob_num = 1;var is_stop = 0//对外⽅法，传⼊⽂件对象this.addFileAndSend = function(that){var file = that.files[0];blob = cutFile(file);sendFile(blob,file);blob_num += 1;}//停⽌⽂件上传this.stop = function(){xhr.abort();is_stop = 1;}//切割⽂件function cutFile(file){var file_blob = file.slice(start,end);start = end;end = start + LENGTH;return file_blob;};//发送⽂件function sendFile(blob,file){var total_blob_num = Math.ceil(file.size / LENGTH);form_data.append('file',blob);form_data.append('blob_num',blob_num);form_data.append('total_blob_num',total_blob_num);form_data.append('file_name',);xhr.open('POST','./upload.php',false);xhr.onreadystatechange = function () {var progress;var progressObj = document.getElementById('finish');if(total_blob_num == 1){progress = '100%';}else{progress = Math.min(100,(blob_num/total_blob_num)* 100 ) +'%';}progressObj.style.width = progress;var t = setTimeout(function(){if(start < file.size && is_stop === 0){blob = cutFile(file);sendFile(blob,file);blob_num += 1;}else{setTimeout(t);}},1000);}xhr.send(form_data);}}</script></body></html>PHP部分代码<?phpclass Upload{private $filepath = './upload'; //上传⽬录private $tmpPath; //PHP⽂件临时⽬录private $blobNum; //第⼏个⽂件块private $totalBlobNum; //⽂件块总数private $fileName; //⽂件名public function __construct($tmpPath,$blobNum,$totalBlobNum,$fileName){ $this->tmpPath = $tmpPath;$this->blobNum = $blobNum;$this->totalBlobNum = $totalBlobNum;$this->fileName = $fileName;$this->moveFile();$this->fileMerge();}//判断是否是最后⼀块，如果是则进⾏⽂件合成并且删除⽂件块private function fileMerge(){if($this->blobNum == $this->totalBlobNum){$blob = '';for($i=1; $i<= $this->totalBlobNum; $i++){$blob .= file_get_contents($this->filepath.'/'. $this->fileName.'__'.$i);}file_put_contents($this->filepath.'/'. $this->fileName,$blob);$this->deleteFileBlob();}}//删除⽂件块private function deleteFileBlob(){for($i=1; $i<= $this->totalBlobNum; $i++){@unlink($this->filepath.'/'. $this->fileName.'__'.$i);}}//移动⽂件private function moveFile(){$this->touchDir();$filename = $this->filepath.'/'. $this->fileName.'__'.$this->blobNum;move_uploaded_file($this->tmpPath,$filename);}//API返回数据public function apiReturn(){if($this->blobNum == $this->totalBlobNum){if(file_exists($this->filepath.'/'. $this->fileName)){$data['code'] = 2;$data['msg'] = 'success';$data['file_path'] = 'http://'.$_SERVER['HTTP_HOST'].dirname($_SERVER['DOCUMENT_URI']).str_replace('.','',$this->filepath).'/'. $this->fileName; }}else{if(file_exists($this->filepath.'/'. $this->fileName.'__'.$this->blobNum)){$data['code'] = 1;$data['msg'] = 'waiting for all';$data['file_path'] = '';}}header('Content-type: application/json');echo json_encode($data);}//建⽴上传⽂件夹private function touchDir(){if(!file_exists($this->filepath)){return mkdir($this->filepath);}}}//实例化并获取系统变量传参$upload = new Upload($_FILES['file']['tmp_name'],$_POST['blob_num'],$_POST['total_blob_num'],$_POST['file_name']);//调⽤⽅法，返回结果$upload->apiReturn();以上就是本⽂的全部内容，希望对⼤家的学习有所帮助，也希望⼤家多多⽀持。
![[转]前端实现文件的断点续传](https://img.taocdn.com/s1/m/29f1bb1611a6f524ccbff121dd36a32d7375c77b.png)
