php 判断上传文件大小的示例代码

代码如下：

<?php
/**
* 判断上传文件大小
* edit www.jb200.com
*/

function imageUpload()
{
if (is_uploaded_file($_FILES['logo']['tmp_name'])) {
    //$_FILES是一个关于图片信息的数组
    $upfile = ($_FILES["logo"]); //赋值
    $suffix=substr($upfile["name"],strrpos($upfile["name"],"."));
    $name = mktime() .rand().$suffix; //原文件名
    $type = $upfile["type"]; //文件类型
    $size = $upfile["size"]; //文件大小
    $tmp_name = $upfile["tmp_name"]; //临时文件名
    $error = $upfile["error"]; //上传相关错误代码
   $str=getimagesize($tmp_name); 
 
   $mode="/width="(.*)" height="(.*)"/";
    preg_match($mode,$str[3],$arr);
    if($arr[1]>120 || $arr[2]>60){

echo "<script>alert('图片过大');</script>";
exit();
    }
       
    switch ($type) {
case 'image/pjpeg' :
    $ok = 1;
    break;
case 'image/jpeg' :
    $ok = 1;
    break;
case 'image/gif' :
    $ok = 1;
    break;
    //case 'image/x-png' :
    //    $ok = 1; //IE为x-png；FOX为png
    //    break;
    }
    if ($ok && $error == '0') {
       move_uploaded_file($tmp_name, "c:/" . $name);
       return $name;
    }
} else {
    return null;
}
}
?>