实现过程：
将文件分割，分片上传，然后合并
前端核心code：
var fileForm = document.getElementById(“file”);
var upstartBtn = document.getElementById(‘upstart’);
var stopBtn = document.getElementById(‘stop’);
var startBtn = document.getElementById(‘restart’);
var rate = document.getElementById(‘rate’);
var divlog = document.getElementById(‘divlog’);
//—————————
const LENGTH = 1024 * 1024 * 1;
var start = 0;
var end = start + LENGTH;
var blob;
var blob_num = 1;
var is_stop = 0
var file = null;
var md5filename = ”;
//—————————–
var upload_instance = new Upload();
fileForm.onchange = function()
{
browserMD5File(fileForm.files[0], function (err, md5) { //如果文件大，md5值生成较慢 md5值生成后才能上传处理，自己优化下吧
md5filename = md5; //如果需要刷新后也能断点，可利用cookie记录，自行完善
divlog.innerHTML = ‘文件md5为：’ + md5filename;
});
}
upstartBtn.onclick = function(){
upload_instance.addFileAndSend(fileForm);
}
stopBtn.onclick = function(){
upload_instance.stop();
}
startBtn.onclick = function(){
upload_instance.start();
}
function Upload(){
var xhr = new XMLHttpRequest();
var form_data = new FormData();
//对外方法，传入文件对象
this.addFileAndSend = function(that){
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;
}
this.start = function(){
sendFile(blob,file);
is_stop = 0;
}
//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(‘md5_file_name’,md5filename);
form_data.append(‘file_name’,file.name);
xhr.open(‘POST’,’./index.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 )).toFixed(2) +’%’;
}
console.log(‘progress—–‘+progress);
progressObj.style.width = progress;
rate.innerHTML = 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);
}
}
后端code
<?php
class 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
private $md5FileName;
public function __construct($tmpPath,$blobNum,$totalBlobNum,$fileName, $md5FileName){
$this->tmpPath = $tmpPath;
$this->blobNum = $blobNum;
$this->totalBlobNum = $totalBlobNum;
$this->fileName = $this->createName($fileName, $md5FileName);
$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);
}
}
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’;
$data[‘file_path’] = ”;
}
}
header(‘Content-type: application/json’);
echo json_encode($data);
}
private function touchDir(){
if(!file_exists($this->filepath)){
return mkdir($this->filepath);
}
}
private function createName($fileName, $md5FileName){
return $md5FileName . ‘.’ . pathinfo($fileName)[‘extension’];
}
}
$upload = new Upload($_FILES[‘file’][‘tmp_name’],$_POST[‘blob_num’],$_POST[‘total_blob_num’],$_POST[‘file_name’],$_POST[‘md5_file_name’]);
$upload->apiReturn();