大文件断点续传

时间:2021-10-26 12:48:20
<!DOCTYPE html>  
<html>
<head>
<meta charset="UTF-8"/>
<title>xhr2</title>
</head>
<body>
<div id="drop_area" style="border:3px dashed silver;width:200px; height:200px">
将图片拖拽到此
</div>

<progress value="0" max="10" id="prouploadfile"></progress>

<span id="persent">0%</span>
<br />
<!--<button onclick="xhr2()">ajax上传</button>-->
<button onclick="stopup()" id="stop">上传</button>
<script>
//拖拽上传开始
//-1.禁止浏览器打开文件行为
document.addEventListener("drop",function(e){ //拖离
e.preventDefault();
})
document.addEventListener("dragleave",function(e){ //拖后放
e.preventDefault();
})
document.addEventListener("dragenter",function(e){ //拖进
e.preventDefault();
})
document.addEventListener("dragover",function(e){ //拖来拖去
e.preventDefault();
})
//上传进度
var pro = document.getElementById('prouploadfile');
var persent = document.getElementById('persent');
function clearpro(){
pro.value=0;
persent.innerHTML="0%";
}

//2.拖拽
var stopbutton = document.getElementById('stop');

var resultfile=""
var box = document.getElementById('drop_area'); //拖拽区域
box.addEventListener("drop",function(e){
var fileList = e.dataTransfer.files; //获取文件对象
console.log(fileList)
//检测是否是拖拽文件到页面的操作
if(fileList.length == 0){
return false;
}
//拖拉图片到浏览器,可以实现预览功能
//规定视频格式
//in_array
Array.prototype.S=String.fromCharCode(2);
Array.prototype.in_array=function(e){
var r=new RegExp(this.S+e+this.S);
return (r.test(this.S+this.join(this.S)+this.S));
};
var video_type=["video/mp4","video/ogg"];

//创建一个url连接,供src属性引用
var fileurl = window.URL.createObjectURL(fileList[0]);
if(fileList[0].type.indexOf('image') === 0){ //如果是图片
var str="<img width='200px' height='200px' src='"+fileurl+"'>";
document.getElementById('drop_area').innerHTML=str;
}else if(video_type.in_array(fileList[0].type)){ //如果是规定格式内的视频
var str="<video width='200px' height='200px' controls='controls' src='"+fileurl+"'></video>";
document.getElementById('drop_area').innerHTML=str;
}else{ //其他格式,输出文件名
//alert("不预览");
var str="文件名字:"+fileList[0].name;
document.getElementById('drop_area').innerHTML=str;
}
resultfile = fileList[0];
console.log(resultfile);

//切片计算
filesize= resultfile.size;
setsize=500*1024;
filecount = filesize/setsize;
//console.log(filecount)
//定义进度条
pro.max=parseInt(Math.ceil(filecount));



i =getCookie(resultfile.name);
i = (i!=null && i!="")?parseInt(i):0

if(Math.floor(filecount)<i){
alert("已经完成");
pro.value=i+1;
persent.innerHTML="100%";

}else{
alert(i);
pro.value=i;
p=parseInt(i)*100/Math.ceil(filecount)
persent.innerHTML=parseInt(p)+"%";
}

},false);

//3.ajax上传

var stop=1;
function xhr2(){
if(stop==1){
return false;
}
if(resultfile==""){
alert("请选择文件")
return false;
}
i=getCookie(resultfile.name);
console.log(i)
i = (i!=null && i!="")?parseInt(i):0

if(Math.floor(filecount)<parseInt(i)){
alert("已经完成");
return false;
}else{
//alert(i)
}
var xhr = new XMLHttpRequest();//第一步
//新建一个FormData对象
var formData = new FormData(); //++++++++++
//追加文件数据

//改变进度条
pro.value=i+1;
p=parseInt(i+1)*100/Math.ceil(filecount)
persent.innerHTML=parseInt(p)+"%";
//进度条


if((filesize-i*setsize)>setsize){
blobfile= resultfile.slice(i*setsize,(i+1)*setsize);
}else{
blobfile= resultfile.slice(i*setsize,filesize);
formData.append('lastone', Math.floor(filecount));
}
formData.append('file', blobfile);
//return false;
formData.append('blobname', i); //++++++++++
   formData.append('filename', resultfile.name); //++++++++++
//post方式
xhr.open('POST', 'xhr2.php'); //第二步骤
//发送请求
xhr.send(formData); //第三步骤
stopbutton.innerHTML = "暂停"
//ajax返回
xhr.onreadystatechange = function(){ //第四步
    if ( xhr.readyState == 4 && xhr.status == 200 ) {
      console.log( xhr.responseText );
if(i<filecount){
xhr2();
}else{
i=0;
}
    }
  };
//设置超时时间
xhr.timeout = 20000;
xhr.ontimeout = function(event){
    alert('请求超时,网络拥堵!低于25K/s');
  }

i=i+1;
setCookie(resultfile.name,i,365)

}

//设置cookie
function setCookie(c_name,value,expiredays)
{
var exdate=new Date()
exdate.setDate(exdate.getDate()+expiredays)
document.cookie=c_name+ "=" +escape(value)+
((expiredays==null) ? "" : ";expires="+exdate.toGMTString()+";path=/")
}
//获取cookie
function getCookie(c_name)
{
if (document.cookie.length>0)
{
c_start=document.cookie.indexOf(c_name + "=")
if (c_start!=-1)
{
c_start=c_start + c_name.length+1
c_end=document.cookie.indexOf(";",c_start)
if (c_end==-1) c_end=document.cookie.length
return unescape(document.cookie.substring(c_start,c_end))
}
}
return ""
}


function stopup(){
if(stop==1){
stop = 0

xhr2();
}else{
stop = 1
stopbutton.innerHTML = "继续"

}

}
</script>
</body>
</html>

php代码

    <?php  
//$name=$_POST['username'];
$dir=$_POST['filename'];
$dir="uploads/".md5($dir);
file_exists($dir) or mkdir($dir,0777,true);


$path=$dir."/".$_POST['blobname'];


//print_r($_FILES["file"]);
move_uploaded_file($_FILES["file"]["tmp_name"],$path);

if(isset($_POST['lastone'])){
echo $_POST['lastone'];
$count=$_POST['lastone'];

$fp = fopen($_POST['filename'],"abw");
for($i=0;$i<=$count;$i++){
$handle = fopen($dir."/".$i,"rb");
fwrite($fp,fread($handle,filesize($dir."/".$i)));
fclose($handle);
}
fclose($fp);
}


?>