在胡说之前，首先声明，本文是建立在掌握php单文件上传的基础上,所以这里就不赘述文件上传服务器配置，表单设置该注意的地方了。
话不多少，直入主题，在请求页面方面有两种写法（只呈现表单部分，以上传三个文件为例。）
<span><</span><span>form </span><span>action</span><span>="doAction.php"</span><span> method</span><span>="post"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span><span> 请选择我的上传文件
</span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfile[]"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="submit"</span><span> value</span><span>="上传"</span><span>/></span><span></</span><span>form</span><span>></span><span><</span><span>form </span><span>action</span><span>="doAction.php"</span><span> method</span><span>="post"</span><span> enctype</span><span>="multipart/form-data"</span><span>></span><span> 请选择我的上传文件
</span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil1"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil2"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="file"</span><span> name</span><span>="myfil3"</span><span>/></span><span><</span><span>input </span><span>type</span><span>="submit"</span><span> value</span><span>="上传"</span><span>/></span><span></</span><span>form</span><span>></span>两个对比，发现仅仅是name的不同，第一个将name设置成数组的形式，而第二个则是我们通常设置也很容易想到的一种方法。
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虽然表面上显示的仅仅有一点点不同，但真正提交到doAction.php页面的$_FILES则有很大不同。
第一种的$_FILES是一个三维数组，而第二种是二维数组，如下：
显然我们处理第二种格式的$_FILES更加方便。当然我们也可以想办法将第一种格式的$_FILES转化为第二种形式，如下：\
<span>function</span><span> getFiles(){
</span><span>foreach</span>(<span>$_FILES</span><span>as</span><span>$file</span><span>){
</span><span>$fileNum</span>=<span>count</span>(<span>$file</span>['name'<span>]);
</span><span>if</span> (<span>$fileNum</span>==1<span>) {
</span><span>$files</span>=<span>$file</span><span>;
}</span><span>else</span><span>{
</span><span>for</span> (<span>$i</span>=0; <span>$i</span> < <span>$fileNum</span>; <span>$i</span>++<span>) {
</span><span>$files</span>[<span>$i</span>]['name']=<span>$file</span>['name'][<span>$i</span><span>];
</span><span>$files</span>[<span>$i</span>]['type']=<span>$file</span>['type'][<span>$i</span><span>];
</span><span>$files</span>[<span>$i</span>]['tmp_name']=<span>$file</span>['tmp_name'][<span>$i</span><span>];
</span><span>$files</span>[<span>$i</span>]['error']=<span>$file</span>['error'][<span>$i</span><span>];
</span><span>$files</span>[<span>$i</span>]['size']=<span>$file</span>['size'][<span>$i</span><span>];
}
}
}
</span><span>return</span><span>$files</span><span>;
}</span>通过这个函数，将$_FILES转化为下面格式:
此刻，两种上传方式已经处在同一起跑线了，下面的工作便是编写uploadFile()函数对每个文件进行上传，这也是本文的重点。
文件上传函数：
<span>function</span> uploadFile(<span>$file</span>,<span>$path</span>='./uploads',<span>$max_size</span>,<span>$allowExt</span><span>){
</span><span>$filename</span>=<span>$file</span>['name'<span>];
</span><span>$type</span>=<span>$file</span>['type'<span>];
</span><span>$temp_name</span>=<span>$file</span>['tmp_name'<span>];
</span><span>$error</span>=<span>$file</span>['error'<span>];
</span><span>$size</span>=<span>$file</span>['size'<span>];
</span><span>if</span> (<span>$error</span>==<span>UPLOAD_ERR_OK) {
</span><span>if</span> (<span>$size</span>><span>$max_size</span><span>) {
</span><span>$res</span>['mes']=<span>$filename</span>."文件超过规定上传大小"<span>;
}
</span><span>$ext</span>=getExt(<span>$filename</span><span>);
</span><span>if</span> (!<span>in_array</span>(<span>$ext</span>, <span>$allowExt</span><span>)) {
</span><span>$res</span>['mes']=<span>$filename</span>.'文件名不合乎规范'<span>;
}
</span><span>if</span> (!<span>is_uploaded_file</span>(<span>$temp_name</span><span>)) {
</span><span>$res</span>['mes']=<span>$filename</span>."文件不是通过HTTP POST 方法上传上传过来的"<span>;
}
</span><span>if</span> (@<span>$res</span><span>) {
</span><span>return</span><span>$res</span><span>;
}
</span><span>if</span> (!<span>file_exists</span>(<span>$path</span><span>)) {
</span><span>mkdir</span>(<span>$path</span>,0777,<span>true</span><span>);
</span><span>chmod</span>(<span>$path</span>, 0777<span>);
}
</span><span>$fname</span>=<span>getUniName();
</span><span>$destination</span>=<span>$path</span>.'/'.<span>$fname</span>.'.'.<span>$ext</span><span>;
</span><span>if</span> (<span>move_uploaded_file</span>(<span>$temp_name</span>, <span>$destination</span><span>)) {
</span><span>$res</span>['mes']=<span>$filename</span>.'上传成功'<span>;
</span><span>$res</span>['dest']=<span>$destination</span><span>;
}</span><span>else</span><span>{
</span><span>$res</span>['mes']=<span>$filename</span>."文件上传失败"<span>;
}
}</span><span>else</span><span>{
</span><span>switch</span> (<span>$error</span><span>) {
</span><span>case</span> '1':
<span>$res</span>['mes']="超过了配置文件上传文件的大小"<span>;
</span><span>break</span><span>;
</span><span>case</span> '2':
<span>$res</span>['mes']="超过表单设置上传文件文件的大小"<span>;
</span><span>break</span><span>;
</span><span>case</span> '3':
<span>$res</span>['mes']="文件部分被上传"<span>;
</span><span>break</span><span>;
</span><span>case</span> '4':
<span>$res</span>['mes']="没有文件被上传"<span>;
</span><span>break</span><span>;
</span><span>case</span> '6':
<span>$res</span>['mes']="没有找到临时目录"<span>;
</span><span>break</span><span>;
</span><span>case</span> '7':
<span>$res</span>['mes']="文件不可写"<span>;
</span><span>break</span><span>;
</span><span>default</span>:
<span>$res</span>['mes']="上传文件失败"<span>;
</span><span>break</span><span>;
}
}
</span><span>return</span><span>$res</span><span>;
}</span>其中还涉及了两个小函数：
<span>/*</span><span>*
* 获得文件扩展名
* @param string $filename 上传文件名
* @return string 返回扩展名
</span><span>*/</span><span>function</span> getExt(<span>$filename</span><span>){
</span><span>$arr</span>=<span>explode</span>('.', <span>basename</span>(<span>$filename</span><span>));
</span><span>return</span><span>end</span>(<span>$arr</span><span>);
}
</span><span>/*</span><span>*
* 获得文件唯一扩展名
* @return string 经过md5后生成32位唯一的上传文件名
</span><span>*/</span><span>function</span><span> getUniName(){
</span><span>return</span><span>md5</span>(<span>uniqid</span>(<span>microtime</span>(<span>true</span>),<span>true</span><span>));
}</span>感受：
很久前接触过php文件上传，当时感觉一团乱麻。现在看来只要掌握$_FILES里面包含什么信息，利用自己写过的知识处理一些小技巧，系统有逻辑的加以考虑，适时地封装函数，以后文件上传就可以很快地展开。这次我展现的代码必然不是能满足任何需要，所以可以适当改造，成为自己的代码。比如如果要求上传文件是图片内容的话，单靠扩展名是绝对不能判断的，还需要利用图片的特性加以验证。
以上就介绍了php文件上传之多文件上传，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。
