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php下载文件强制任意文件格式下载_PHP教程

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Jul 13, 2016 am 10:30 AM

用php下载一些文件，一般就是为了隐藏文件的真实下载地址才需要这样，否则这样会增加服务器负担，不如直接提供软件的地址。

一个简单的php文件下载源代码，虽不支持断点续传等，但是可以满足一些常用的需求了。php下载文件其实用一个a标签就能实现，比如 magento-1.8.1.0.zip 。但是遇到一些浏览器能识别的格式，比如.txt,.html,.pdf等，再用abc.txt 想必也知道会发生什么了。

<?<span>php 
</span><span>/*</span><span>*
* 文件下载
*
*</span><span>*/</span>
<span>header</span>("Content-type:text/html;charset=utf-8"<span>);
download(</span>'web/magento-1.8.1.0.zip', 'magento下载'<span>); 
</span><span>function</span> download(<span>$file</span>, <span>$down_name</span><span>){
</span><span>$suffix</span> = <span>substr</span>(<span>$file</span>,<span>strrpos</span>(<span>$file</span>,'.')); <span>//</span><span>获取文件后缀</span>
<span>$down_name</span> = <span>$down_name</span>.<span>$suffix</span>; <span>//</span><span>新文件名，就是下载后的名字
//判断给定的文件存在与否 </span>
<span>if</span>(!<span>file_exists</span>(<span>$file</span><span>)){
</span><span>die</span>("您要下载的文件已不存在，可能是被删除"<span>);
} 
</span><span>$fp</span> = <span>fopen</span>(<span>$file</span>,"r"<span>);
</span><span>$file_size</span> = <span>filesize</span>(<span>$file</span><span>);
</span><span>//</span><span>下载文件需要用到的头</span>
<span>header</span>("Content-type: application/octet-stream"<span>);
</span><span>header</span>("Accept-Ranges: bytes"<span>);
</span><span>header</span>("Accept-Length:".<span>$file_size</span><span>);
</span><span>header</span>("Content-Disposition: attachment; filename=".<span>$down_name</span><span>);
</span><span>$buffer</span> = 1024<span>;
</span><span>$file_count</span> = 0<span>;
</span><span>//</span><span>向浏览器返回数据 </span>
<span>while</span>(!<span>feof</span>(<span>$fp</span>) && <span>$file_count</span> < <span>$file_size</span><span>){
</span><span>$file_con</span> = <span>fread</span>(<span>$fp</span>,<span>$buffer</span><span>);
</span><span>$file_count</span> += <span>$buffer</span><span>;
</span><span>echo</span> <span>$file_con</span><span>;
} www.jbxue.com
</span><span>fclose</span>(<span>$fp</span><span>);
}
</span>?>

PHP强制性文件下载的源代码

为用户提供强制性的文件下载功能。

<span>/*</span><span>*******************
*@file - path to file
</span><span>*/</span>
<span>function</span> force_download(<span>$file</span><span>)
{
</span><span>if</span> ((<span>isset</span>(<span>$file</span>))&&(<span>file_exists</span>(<span>$file</span><span>))) {
</span><span>header</span>("Content-length: ".<span>filesize</span>(<span>$file</span><span>));
</span><span>header</span>('Content-Type: application/octet-stream'<span>);
</span><span>header</span>('Content-Disposition: attachment; filename="' . <span>$file</span> . '"'<span>);
</span><span>readfile</span>("<span>$file</span>"<span>);
} </span><span>else</span><span> {
</span><span>echo</span> "No file selected"<span>;
}
}</span>

你一定会笑我"下载文件"如此简单都值得说？当然并不是想象那么简单。例如你希望客户要填完一份表格，才可以下载某一文件，你第一个想法一定是用 "Redirect"的方法，先检查表格是否已经填写完毕和完整，然后就将网址指到该文件，这样客户才能下载，但如果你想做一个关于"网上购物"的电子商务网站，考虑安全问题，你不想用户直接复制网址下载该文件，笔者建议你使用PHP直接读取该实际文件然后下载的方法去做。程序如下：

<span>$file_name</span> = "info_check.exe"<span>;
</span><span>$file_dir</span> = "/public/www/download/"<span>;
</span><span>if</span> (!<span>file_exists</span>(<span>$file_dir</span> . <span>$file_name</span>)) { <span>//</span><span>检查文件是否存在</span>
<span>echo</span> "文件找不到"<span>;
</span><span>exit</span><span>;
} </span><span>else</span><span> {
</span><span>$file</span> = <span>fopen</span>(<span>$file_dir</span> . <span>$file_name</span>,"r"); <span>//</span><span> 打开文件
// 输入文件标签 www.jbxue.com</span>
<span>Header</span>("Content-type: application/octet-stream"<span>);
</span><span>Header</span>("Accept-Ranges: bytes"<span>);
</span><span>Header</span>("Accept-Length: ".<span>filesize</span>(<span>$file_dir</span> . <span>$file_name</span><span>));
</span><span>Header</span>("Content-Disposition: attachment; filename=" . <span>$file_name</span><span>);
</span><span>//</span><span> 输出文件内容</span>
<span>echo</span> <span>fread</span>(<span>$file</span>,<span>filesize</span>(<span>$file_dir</span> . <span>$file_name</span><span>));
</span><span>fclose</span>(<span>$file</span><span>);
</span><span>exit</span><span>;
} </span>

而如果文件路径是"http" 或者 "ftp" 网址的话，则源代码会有少许改变，程序如下：

<span>$file_name</span> = "info_check.exe"<span>;
</span><span>$file_dir</span> = "http://www.jbxue.com/"<span>;
</span><span>$file</span> = @ <span>fopen</span>(<span>$file_dir</span> . <span>$file_name</span>,"r"<span>);
</span><span>if</span> (!<span>$file</span><span>) {
</span><span>echo</span> "文件找不到"<span>;
} </span><span>else</span><span> {
</span><span>Header</span>("Content-type: application/octet-stream"<span>);
</span><span>Header</span>("Content-Disposition: attachment; filename=" . <span>$file_name</span><span>);
</span><span>while</span> (!<span>feof</span> (<span>$file</span><span>)) {
</span><span>echo</span> <span>fread</span>(<span>$file</span>,50000<span>);
}
</span><span>fclose</span> (<span>$file</span><span>);
} </span>

这样就可以用PHP直接输出文件了。

但，一定要注意：Header信息相当于先将文件信息高速浏览器，然后，再把浏览器上的信息下载到附件中。所以，如果在MVC模式的应用程序中，view页一定不要有任何内容，否则，view页的相关内容会随着文件的内容一同被下载，导致下载后的文件不能使用。
下面是我的程序：

<span>public</span> <span>function</span><span> downloadAction()
{
</span><span>if</span> (<span>isset</span>(<span>$_GET</span>['mriID'<span>]))
{
</span><span>$this</span>->view->mriID=(<span>get_magic_quotes_gpc</span>())?<span>$_GET</span>['mriID']:<span>addslashes</span>(<span>$_GET</span>['mriID'<span>]);
}
</span><span>if</span> (<span>isset</span>(<span>$_GET</span>['dicomID'<span>]))
{
</span><span>$this</span>->view->dicomID=(<span>get_magic_quotes_gpc</span>())?<span>$_GET</span>['dicomID']:<span>addslashes</span>(<span>$_GET</span>['dicomID'<span>]);
}
</span><span>if</span> (<span>isset</span>(<span>$_GET</span>['JPGID'<span>]))
{
</span><span>$this</span>->view->JPGID=(<span>get_magic_quotes_gpc</span>())?<span>$_GET</span>['JPGID']:<span>addslashes</span>(<span>$_GET</span>['JPGID'<span>]);
} www.jbxue.com
</span><span>$dicomfile</span>=<span>new</span><span> dicomfile(); 
</span><span>$jpgfile</span>=<span>new</span><span> jpgfile();
</span><span>$mri</span>=<span>new</span><span> mri();
</span><span>if</span>(<span>$this</span>->view-><span>dicomID)
{
</span><span>$filename</span>=<span>$dicomfile</span>->find(<span>$this</span>->view->dicomID)-><span>toArray();
</span><span>$filename</span>=<span>$filename</span>[0]['filename'<span>];
} 
</span><span>else</span> <span>if</span>(<span>$this</span>->view-><span>JPGID)
{
</span><span>$filename</span>=<span>$jpgfile</span>->find(<span>$this</span>->view->JPGID)-><span>toArray();
</span><span>$filename</span>=<span>$filename</span>[0]['JPGname'<span>];
}
</span><span>$dir</span>=<span>$mri</span>->find(<span>$this</span>->view->mriID)-><span>toArray();
</span><span>$dir</span>=<span>$dir</span>[0]['dicom_path'<span>];
</span><span>$file</span>=<span>$dir</span>.'/'.<span>$filename</span><span>;
</span><span>if</span> (!<span>file_exists</span>(<span>$file</span><span>))
{
</span><span>echo</span> "the file does not exist!"<span>;
</span><span>exit</span><span>();
}
</span><span>$file_size</span>=<span>filesize</span>(<span>$file</span><span>);
</span><span>header</span>("Content-type: application/octet-stream"<span>);
</span><span>header</span>("Accept-Ranges: bytes"<span>);
</span><span>header</span>("Accept-Length:". <span>$file_size</span><span>);
</span><span>header</span>("Content-Disposition: attachment; filename=".<span>$filename</span><span>); 
</span><span>$fp</span>=<span>fopen</span>(<span>$file</span>,"r"<span>);
</span><span>if</span> (!<span>$fp</span><span>)
</span><span>echo</span> "can't open file!"<span>;
</span><span>$buffer_size</span>=1024<span>;
</span><span>$cur_pos</span>=0<span>;
</span><span>while</span> (!<span>feof</span>(<span>$fp</span>)&&<span>$file_size</span>-<span>$cur_pos</span>><span>$buffer_size</span><span>)
{
</span><span>$buffer</span>=<span>fread</span>(<span>$fp</span>,<span>$buffer_size</span><span>);
</span><span>echo</span> <span>$buffer</span><span>;
</span><span>$cur_pos</span>+=<span>$buffer_size</span><span>;
}
</span><span>$buffer</span>=<span>fread</span>(<span>$fp</span>,<span>$file_size</span>-<span>$cur_pos</span><span>);
</span><span>echo</span> <span>$buffer</span><span>;
</span><span>fclose</span>(<span>$fp</span><span>); 
}</span>

此时，download.phtml页面一定要是完全空白的。千万不要有任何内容（包括如下的固定信息：

<!DOCTYPE html <span>PUBLIC</span> "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>）否则，这些信息都将被下载到下载文件中，导致文件不能使用。

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