php实现文件的上传和下载

实现的上传的步骤第一步：设计上传页面
第二步：$_files 数组
第三步：is_uploaded_file();

<phpif(is_uploaded_file($_FILES['file']['tmp_name'])) 第一步先检测： is_uploaded_file
{
$upfiles=$_FILES['file'];
$name=$upfiles['name'];
$type=$upfiles['type'];
$error=$upfiles['error'];
$tmp_name=$upfiles['tmp_name'];
$size=$upfiles['size'];

switch($type){

case 'image/png':


$a=1;

break;

case 'image/jpeg':

$a=0;

break;
}
}
//move_uploaded_file  
if($a && $error==0){
  move_uploaded_file($tmp_name,'test/'.$name);
  echo "OK!";
}

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


</form>