PHP大文件分片上传

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

前端代码


<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>Documenttitle>
    <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="./index.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',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 ) +'%';
                }
                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代码


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

    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();

转载自:https://www.cnblogs.com/2017sss/p/6654659.html

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