php文件上传实例（带文件类型限制）

<?php
$uptype=array("jar","zip");
//允许上传文件类型
$max_file_size=20480000;   //上传文件大小限制, 单位BYTE
$path_parts=pathinfo($_SERVER['PHP_SELF']); //取得当前路径
$destination_folder="files/";
//上传文件路径
$name="MuXi_".date("Y-m-d_H-i-s");
//保存文件名
if($_SERVER['REQUEST_METHOD'] == 'POST')
{
$file = $_FILES["upload_file"];
if(!is_uploaded_file($file["tmp_name"]))
//是否存在文件
{
echo "文件不存在！";
exit;
}
$torrent = explode(".", $file["name"]);
$fileend = end($torrent);
$fileend = strtolower($fileend);
if(!in_array($fileend, $uptype))
//检查上传文件类型
{
echo"不允许上传此类型文件！";
exit;
}
if($max_file_size < $file["size"])
//检查文件大小
{
echo "文件太大，超过上传限制！";
exit;
}
if(!file_exists($destination_folder))
mkdir($destination_folder);
$filename=$file["tmp_name"];
$image_size = getimagesize($filename);
$pinfo=pathinfo($file["name"]);
$ftype=$pinfo[extension];
$destination = $destination_folder.$name.".".$ftype;
if(file_exists($destination) && $overwrite != true)
{
echo "同名文件已经存在了！";
exit;
}
if(!move_uploaded_file ($filename, $destination))
{
echo "移动文件出错！";
exit;
}
$pinfo=pathinfo($destination);
$fname=$pinfo[basename];
echo "上传成功！";
}
?>

<form action="up.php" method="post" enctype="multipart/form-data">
<input type="file" name="upload_file" />
<input type="submit" value="上传" />