PHP file upload related restrictions

Upload related restrictions

1 Client restrictions

<form action="doAction2.php" method="post" enctype="multipart/form-data">
<input type="hidden" name="MAX_FILE_SIZE" value="101321" />
请选择您要上传的文件：
<input type="file" name="myFile" accept="image/jpeg,image/gif,text/html"/><br/>
<input type="submit" value="上传"/>
</form>

The input attributes are used to limit the size and type of uploaded files, but personal feelings: First, the html code is "visible "; Second, it often doesn't work (I didn't find the reason, but because of the first one I also want to give up on it, just know it.

2 Server-side restrictions

Main restrictions on size and type , and then there is the method.

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);
//接受文件，临时文件信息
$fileinfo=$_FILES["myFile"];//降维操作
$filename=$fileinfo["name"];
$tmp_name=$fileinfo["tmp_name"];
$size=$fileinfo["size"];
$error=$fileinfo["error"];
$type=$fileinfo["type"];
//服务器端设定限制
$maxsize=10485760;//10M,10*1024*1024
$allowExt=array(&#39;jpeg&#39;,&#39;jpg&#39;,&#39;png&#39;,&#39;tif&#39;);//允许上传的文件类型（拓展名
$ext=pathinfo($filename,PATHINFO_EXTENSION);//提取上传文件的拓展名
//目的信息
$path="uploads";
if (!file_exists($path)) {   //当目录不存在，就创建目录
    mkdir($path,0777,true);
    chmod($path, 0777);
}
//$destination=$path."/".$filename;
//得到唯一的文件名！防止因为文件名相同而产生覆盖
$uniName=md5(uniqid(microtime(true),true)).$ext;//md5加密，uniqid产生唯一id，microtime做前缀
if ($error==0) {
    if ($size>$maxsize) {
        exit("上传文件过大！");
    }
    if (!in_array($ext, $allowExt)) {
        exit("非法文件类型");
    }
    if (!is_uploaded_file($tmp_name)) {
        exit("上传方式有误，请使用post方式");
    }
    if (@move_uploaded_file($tmp_name, $uniName)) {//@错误抑制符，不让用户看到警告
        echo "文件".$filename."上传成功!";
    }else{
        echo "文件".$filename."上传失败!";
    }
    //判断是否为真实图片（防止伪装成图片的病毒一类的
    if (!getimagesize($tmp_name)) {//getimagesize真实返回数组，否则返回false
        exit("不是真正的图片类型");
    }
}else{
    switch ($error){
        case 1:
            echo "超过了上传文件的最大值，请上传2M以下文件";
            break;
        case 2:
            echo "上传文件过多，请一次上传20个及以下文件！";
            break;
        case 3:
            echo "文件并未完全上传，请再次尝试！";
            break;
        case 4:
            echo "未选择上传文件！";
            break;
        case 7:
            echo "没有临时文件夹";
            break;
    }
}

Here, the specific implementation is commented, you can actually try it yourself, it is very interesting

3 Encapsulation

Function

<?php
function uploadFile($fileInfo,$path,$allowExt,$maxSize){
$filename=$fileInfo["name"];
$tmp_name=$fileInfo["tmp_name"];
$size=$fileInfo["size"];
$error=$fileInfo["error"];
$type=$fileInfo["type"];
//服务器端设定限制
$ext=pathinfo($filename,PATHINFO_EXTENSION);
//目的信息
if (!file_exists($path)) {   
    mkdir($path,0777,true);
    chmod($path, 0777);
}
$uniName=md5(uniqid(microtime(true),true)).&#39;.&#39;.$ext;
$destination=$path."/".$uniName;
if ($error==0) {
    if ($size>$maxSize) {
        exit("上传文件过大！");
    }
    if (!in_array($ext, $allowExt)) {
        exit("非法文件类型");
    }
    if (!is_uploaded_file($tmp_name)) {
        exit("上传方式有误，请使用post方式");
    }
    //判断是否为真实图片（防止伪装成图片的病毒一类的
    if (!getimagesize($tmp_name)) {//getimagesize真实返回数组，否则返回false
        exit("不是真正的图片类型");
    }
    if (@move_uploaded_file($tmp_name, $destination)) {//@错误抑制符，不让用户看到警告
        echo "文件".$filename."上传成功!";
    }else{
        echo "文件".$filename."上传失败!";
    }
    
}else{
    switch ($error){
        case 1:
            echo "超过了上传文件的最大值，请上传2M以下文件";
            break;
        case 2:
            echo "上传文件过多，请一次上传20个及以下文件！";
            break;
        case 3:
            echo "文件并未完全上传，请再次尝试！";
            break;
        case 4:
            echo "未选择上传文件！";
            break;
        case 7:
            echo "没有临时文件夹";
            break;
    }
}
return $destination;
}

call

<?php
header(&#39;content-type:text/html;charset=utf-8&#39;);
$fileInfo=$_FILES["myFile"];
$maxSize=10485760;//10M,10*1024*1024
$allowExt=array(&#39;jpeg&#39;,&#39;jpg&#39;,&#39;png&#39;,&#39;tif&#39;);
$path="uploads";
include_once &#39;upFunc.php&#39;;
uploadFile($fileInfo, $path, $allowExt, $maxSize);

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