form.php
<html> <body> <form action="upload.php" method="post" enctype="multipart/form-data"> <label for="file">上传：</label> <input type="file" name="file" id="file" /> <input type="submit" name="submit" value="上传" /> </form> </body> </html>
upload.php
<?php
//Set the upload file size limit (unit b)
$max_size=500000;
//Set the file format limit for uploaded files
$format=array("image/jpeg","image/gif","image/png");
//File upload directory
$dir=dirname(__FILE__) ."/upload/";
//name of the uploaded file
$name=$_FILES["file"]["name"];
//Type of uploaded file
$type=$_FILES["file"]["type"];
//The size of the uploaded file, in bytes
$size=$_FILES["file"]["size"];
//name of temporary copy of file stored on server
$tmp_name=$_FILES["file"]["tmp_name"];
//Error code caused by file upload
$error=$_FILES["file"]["error"];
//determine file size
if($size>$max_size){
exit("The file size exceeds the maximum value");
}
// Determine the file format
if(!in_array($type,$format)){
exit("Invalid file format");
}
/ / Determine the upload directory, create it if it does not exist
if(!is_dir($dir)){
mkdir ($ dir, true);
}
//generate filename
date_default_timezone_set("PRC");
$file_name=time().mt_rand(1111, 999999);
//get file format
$ext=substr($type, strpos($type, "/")+1);
if($error>0){
exit($error);
}else{
if(move_uploaded_file($tmp_name, $dir.$file_name.".".$ext)){
exit("Upload successful");
}
}