PHP文件上传及下载源码，

PHP文件上传及下载源码，

　　一、文件上传

　　前台页面：

<span><!</span><span>DOCTYPE html</span><span>></span>
<span><</span><span>html</span><span>></span>
<span><</span><span>head</span><span>></span>
    <span><</span><span>meta </span><span>charset</span><span>="utf-8"</span><span>></span>
    <span><</span><span>title</span><span>></span>文件上传<span></</span><span>title</span><span>></span>
<span></</span><span>head</span><span>></span>
<span><</span><span>body</span><span>></span>
<span><</span><span>div</span><span>></span>
    <span><</span><span>form </span><span>method</span><span>="post"</span><span> action</span><span>="upload.php"</span><span> enctype</span><span>="multipart/form-data"</span> <span>></span><span>
        用户名</span><span><</span><span>input </span><span>type</span><span>="text"</span><span> name</span><span>="username"</span><span>></</span><span>input</span><span>></span>
        <span><</span><span>br</span><span>></span><span>
        文件简单介绍</span><span><</span><span>br</span><span>><</span><span>textarea </span><span>name</span><span>="fileintro"</span><span> rows</span><span>="8"</span><span> cols</span><span>="50"</span><span>></</span><span>textarea</span><span>></span>
        <span><</span><span>br</span><span>></span>选择要上传的文件<span><</span><span>br</span><span>><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile"</span><span>></</span><span>input</span><span>><</span><span>br</span><span>></span>
        <span><</span><span>input </span><span>type</span><span>="submit"</span><span> value</span><span>="上传文件"</span><span>></</span><span>input</span><span>></span>
    <span></</span><span>form</span><span>></span>
<span></</span><span>div</span><span>></span>
<span></</span><span>body</span><span>></span>
<span></</span><span>html</span><span>></span>

　　后台处理：

<?<span>php
</span><span>//</span><span>接收提交页面传送的相关信息</span>
<span>$name</span> = <span>$_POST</span>['username'<span>];
</span><span>$intro</span> = <span>$_POST</span>['fileintro'<span>];
</span><span>//</span><span>$_FILES中存放着文件的相关信息
// echo "<pre class="brush:php;toolbar:false">";
// print_r($_FILES);
// echo "

"; //可以在这里对文件大小进行限制 /*$filesize = $_FILES['myfile']['size']; if($filesize>2*1024*1024){ echo "文件过大，不能上传"; exit(); }*/ //可以对文件类型进行限制 /*$filetype = $_FILES['myfile']['type']; if($filetype!='image/jpg'&&$filetype!='application/pdf'){ echo "文件类型只能是jpg和pdf"; exit(); }*/ if (is_uploaded_file($_FILES['myfile']['tmp_name'])) { //把文件转存到你希望存放的目录 $uploaded = $_FILES['myfile']['tmp_name']; //每个用户动态创建一个文件夹 $userpath = $_SERVER['DOCUMENT_ROOT']."/up/".$name; //判断该用户是否已经有文件夹 if(!file_exists($userpath)){ mkdir($userpath); } //防止同一用户上传同名文件，可在文件中添加时间戳。 //$moveto = $userpath."/".time().$_FILES['myfile']['name']; //或者对文件名进行修改，但是需要使用字符串处理截得文件后缀名 $truename = $_FILES['myfile']['name']; $moveto = $userpath."/".time().substr($truename,strrpos($truename,".")); if(move_uploaded_file($uploaded,iconv("utf-8", "gb2312", $moveto))){ echo "上传文件".$_FILES['myfile']['name']."成功"; }else{ echo "上传文件".$_FILES['myfile']['name']."失败"; } }else{ echo "上传文件".$FILES['myfile']['name']."失败"; } ?>

　　二、文件下载：

　　单文件下载：

 <?<span>php
    </span><span>function</span> down_file(<span>$file_name</span>,<span>$file_path</span><span>){
    </span><span>//</span><span>$file_name = iconv("uft-8","gb2312",$file_name);    //如果文件名是中文，需要对中文名称转码gb2312
    //要下载的文件读取到服务器的内存中
    //服务器返回文件数据给浏览器
    //浏览器将文件写入用户指定的位置
    //1.判断文件是否存在</span>
    <span>if</span>(!<span>file_exists</span>(<span>$file_name</span><span>)){
        </span><span>echo</span> "111"<span>;
        </span><span>return</span><span> ;
    }
    </span><span>$fp</span> = <span>fopen</span>(<span>$file_name</span>,"r"<span>);
    </span><span>$file_size</span> = <span>filesize</span>(<span>$file_name</span><span>);
    </span><span>//</span><span>获取文件大小
    //可通过file_size限制浏览器下载文件大小。
    //返回的文件</span>
    <span>header</span>("Content-type:application/octet-stream"<span>);
    </span><span>//</span><span>按字节大小返回</span>
    <span>header</span>("Accept-Ranges:bytes"<span>);
    </span><span>//</span><span>返回文件大小</span>
    <span>header</span>("Accept-Length:<span>$file_size</span>"<span>);
    </span><span>//</span><span>客户端弹出对话框，对应的文件名</span>
    <span>header</span>("Content-Disposition:attachment;filename=".<span>$file_name</span><span>);
    </span><span>$buffer</span> = 1024<span>;  
    </span><span>//</span><span>定义缓冲区
    //为了下载的安全，最好使用文件字节读取计数器</span>
    <span>$file_count</span> = 0<span>;
    </span><span>//</span><span>feof用于判断文件是否读取到文档尾</span>
    <span>while</span>(!<span>feof</span>(<span>$fp</span>) && (<span>$file_size</span>-<span>$file_count</span>>0<span>)){
    </span><span>$file_data</span> = <span>fread</span>(<span>$fp</span>,<span>$buffer</span><span>);
    </span><span>//</span><span>统计读了多少个字节</span>
    <span>$file_count</span>+<span>$buffer</span><span>;
    </span><span>echo</span> <span>$file_data</span><span>;   
    </span><span>//</span><span>把部分数据会送给浏览器</span>
<span>    }
    </span><span>fclose</span>(<span>$fp</span><span>);
    </span><span>//</span><span>关闭文件</span>
<span>    }
</span>?>

　　多个文件下载：

　　DownList.php:

<a href="downprocess.php?filename=1.jpg">down</a><img  src="1.jpg"    style="max-width:90%" height="50px" alt="PHP文件上传及下载源码，" ><br><br>
<a href="downprocess.php?filename=2.jpg">down</a><img  src="2.jpg"    style="max-width:90%" height="50px" alt="PHP文件上传及下载源码，" ><br><br>
<a href="downprocess.php?filename=3.jpg">down</a><img  src="3.jpg"    style="max-width:90%" height="50px" alt="PHP文件上传及下载源码，" ><br><br>
<a href="downprocess.php?filename=4.jpg">down</a><img  src="4.jpg"    style="max-width:90%" height="50px" alt="PHP文件上传及下载源码，" ><br><br>

　　downprocess.php:

<?<span>php
    </span><span>$filename</span> = <span>$_REQUEST</span>['filename'<span>];
    </span><span>function</span> down_file(<span>$file_name</span><span>){

    </span><span>if</span>(!<span>file_exists</span>(<span>$file_name</span><span>)){
        </span><span>echo</span> "111"<span>;
        </span><span>return</span><span> ;
    }
    </span><span>$fp</span> = <span>fopen</span>(<span>$file_name</span>,"r"<span>);
    </span><span>$file_size</span> = <span>filesize</span>(<span>$file_name</span><span>);
    </span><span>header</span>("Content-type:application/octet-stream"<span>);
    </span><span>//</span><span>按字节大小返回</span>
    <span>header</span>("Accept-Ranges:bytes"<span>);
    </span><span>//</span><span>返回文件大小</span>
    <span>header</span>("Accept-Length:<span>$file_size</span>"<span>);
    </span><span>//</span><span>客户端弹出对话框，对应的文件名</span>
    <span>header</span>("Content-Disposition:attachment;filename=".<span>$file_name</span><span>);
    </span><span>$buffer</span> = 1024<span>;  
    </span><span>//</span><span>定义缓冲区</span>
    <span>$file_count</span> = 0<span>;
    </span><span>//</span><span>feof用于判断文件是否读取到文档尾</span>
    <span>while</span>(!<span>feof</span>(<span>$fp</span>) && (<span>$file_size</span>-<span>$file_count</span>>0<span>)){
        </span><span>$file_data</span> = <span>fread</span>(<span>$fp</span>,<span>$buffer</span><span>);
        </span><span>//</span><span>统计读了多少个字节</span>
        <span>$file_count</span>+<span>$buffer</span><span>;
        </span><span>echo</span> <span>$file_data</span><span>;   
        </span><span>//</span><span>把部分数据会送给浏览器</span>
<span>        }
    </span><span>fclose</span>(<span>$fp</span><span>);
    }
    down_file(</span><span>$filename</span><span>);
</span>?>