php中正则匹配用户密码

<?php
//密码验证
$password = "zongzi_Abc_oo13a2";
$n = preg_match_all("/^[a-zA-Zd_]{8,}$/",$password,$array);
//长度是8或更多
var_dump($array);
?>

<?php
echo substr("Hello world!",6);
?>

输出：

world!

echo substr('中国文',1);

<?php
$str = '这样一来我的字符串就不会有乱码^_^';

echo "mb_substr:" . mb_substr($str, 0, 7, 'utf-8');
//结果：这样一来我的字
echo "<br>";

echo "mb_strcut:" . mb_strcut($str, 0, 6, 'utf-8');
//结果：这样
?>

function msubstr($str, $start, $len) {
  $tmpstr = "";
  $strlen = $start + $len;
  for($i = 0; $i < $strlen; $i++) {
   if(ord(substr($str, $i, 1)) > 0xa0) {
    $tmpstr .= substr($str, $i, 2);
    $i++;
   } else
    $tmpstr .= substr($str, $i, 1);
  }
  return $tmpstr;
 }

<?php
$filename = "中文 文件名.txt";
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename=' . $filename);
print "Hello!";
?>

<?php
    $file = "/tmp/中文名.tar.gz";

    $filename = basename($file);

    header("Content-type: application/octet-stream");

    //处理中文文件名
    $ua = $_SERVER["HTTP_USER_AGENT"];
    $encoded_filename = urlencode($filename);
    $encoded_filename = str_replace("+", "%20", $encoded_filename);
    if (preg_match("/MSIE/", $ua)) {
     header('Content-Disposition: attachment; filename="' . $encoded_filename . '"');
    } else if (preg_match("/Firefox/", $ua)) {
     header("Content-Disposition: attachment; filename*="utf8''" . $filename . '"');
    } else {
     header('Content-Disposition: attachment; filename="' . $filename . '"');
    }

    header('Content-Disposition: attachment; filename="' . $filename . '"');
    header("Content-Length: ". filesize($file));
    readfile($file);
?>

<?php

trim 去除一个字符串两端空格，
rtrim 是去除一个字符串右部空格，
ltrim 是去除一个字符串左部空格。

echo trim(" 空格 ")."<br>";
echo rtrim(" 空格 ")."<br>";
echo ltrim(" 空格 ")."<br>";

?>

function trimall($str)//删除空格
{
 $qian=array(" ","　","t","n","r");
         $hou=array("","","","","");
 return str_replace($qian,$hou,$str); 
}

$str = " This line containstliberal rn use of whitespace.nn";

// First remove the leading/trailing whitespace
//去掉开始和结束的空白
$str = trim($str);

// Now remove any doubled-up whitespace
//去掉跟随别的挤在一块的空白
$str = preg_replace('/s(?=s)/', '', $str);

// Finally, replace any non-space whitespace, with a space
//最后，去掉非space 的空白，用一个空格代替
$str = preg_replace('/[nrt]/', ' ', $str);

// Echo out: 'This line contains liberal use of whitespace.'
echo "<pre>{$str}</pre>";

$finfo    = finfo_open(FILEINFO_MIME);
$mimetype = finfo_file($finfo, $filename);
finfo_close($finfo);

<?php
$mime = array (
  //applications
  'ai'    => 'application/postscript',
  'eps'   => 'application/postscript',
  'exe'   => 'application/octet-stream',
  'doc'   => 'application/vnd.ms-word',
  'xls'   => 'application/vnd.ms-excel',
  'ppt'   => 'application/vnd.ms-powerpoint',
  'pps'   => 'application/vnd.ms-powerpoint',
  'pdf'   => 'application/pdf',
  'xml'   => 'application/xml',
  'odt'   => 'application/vnd.oasis.opendocument.text',
  'swf'   => 'application/x-shockwave-flash',
  // archives
  'gz'    => 'application/x-gzip',
  'tgz'   => 'application/x-gzip',
  'bz'    => 'application/x-bzip2',
  'bz2'   => 'application/x-bzip2',
  'tbz'   => 'application/x-bzip2',
  'zip'   => 'application/zip',
  'rar'   => 'application/x-rar',
  'tar'   => 'application/x-tar',
  '7z'    => 'application/x-7z-compressed',
  // texts
  'txt'   => 'text/plain',
  'php'   => 'text/x-php',
  'html'  => 'text/html',
  'htm'   => 'text/html',
  'js'    => 'text/javascript',
  'css'   => 'text/css',
  'rtf'   => 'text/rtf',
  'rtfd'  => 'text/rtfd',
  'py'    => 'text/x-python',
  'java'  => 'text/x-java-source',
  'rb'    => 'text/x-ruby',
  'sh'    => 'text/x-shellscript',
  'pl'    => 'text/x-perl',
  'sql'   => 'text/x-sql',
  // images
  'bmp'   => 'image/x-ms-bmp',
  'jpg'   => 'image/jpeg',
  'jpeg'  => 'image/jpeg',
  'gif'   => 'image/gif',
  'png'   => 'image/png',
  'tif'   => 'image/tiff',
  'tiff'  => 'image/tiff',
  'tga'   => 'image/x-targa',
  'psd'   => 'image/vnd.adobe.photoshop',
  //audio
  'mp3'   => 'audio/mpeg',
  'mid'   => 'audio/midi',
  'ogg'   => 'audio/ogg',
  'mp4a'  => 'audio/mp4',
  'wav'   => 'audio/wav',
  'wma'   => 'audio/x-ms-wma',
  // video
  'avi'   => 'video/x-msvideo',
  'dv'    => 'video/x-dv',
  'mp4'   => 'video/mp4',
  'mpeg'  => 'video/mpeg',
  'mpg'   => 'video/mpeg',
  'mov'   => 'video/quicktime',
  'wm'    => 'video/x-ms-wmv',
  'flv'   => 'video/x-flv',
  'mkv'   => 'video/x-matroska'
  );

function _getMimeDetect() {
 if (class_exists('finfo')) {
  return 'finfo';
 } else if (function_exists('mime_content_type')) {
  return 'mime_content_type';
 } else if ( function_exists('exec')) {
  $result = exec('file -ib '.escapeshellarg(__FILE__));
  if ( 0 === strpos($result, 'text/x-php') OR 0 === strpos($result, 'text/x-c++')) {
   return 'linux';
  }
  $result = exec('file -Ib '.escapeshellarg(__FILE__));
  if ( 0 === strpos($result, 'text/x-php') OR 0 === strpos($result, 'text/x-c++')) {
   return 'bsd';
  }
 }
 return 'internal';
}

function _getMimeType($path) {
 global $mime;
 $fmime = _getMimeDetect();
 switch($fmime) {
  case 'finfo':
   $finfo = finfo_open(FILEINFO_MIME);
   if ($finfo)
    $type = @finfo_file($finfo, $path);
   break;
  case 'mime_content_type':
   $type = mime_content_type($path);
   break;
  case 'linux':
   $type = exec('file -ib '.escapeshellarg($path));
   break;
  case 'bsd':
   $type = exec('file -Ib '.escapeshellarg($path));
   break;
  default:
   $pinfo = pathinfo($path);
   $ext = isset($pinfo['extension']) ? strtolower($pinfo['extension']) : '';
   $type = isset($mime[$ext]) ? $mime[$ext] : 'unkown';
   break;
 }
 $type = explode(';', $type);
 
 //需要加上这段，因为如果使用mime_content_type函数来获取一个不存在的$path时会返回'application/octet-stream'
 if ($fmime != 'internal' AND $type[0] == 'application/octet-stream') {
  $pinfo = pathinfo($path);
  $ext = isset($pinfo['extension']) ? strtolower($pinfo['extension']) : '';
  if (!empty($ext) AND !empty($mime[$ext])) {
   $type[0] = $mime[$ext];
  }
 }
 
 return $type[0];
}

$path = '1.txt';  //实际上当前路径并不存在1.txt
var_dump(_getMimeType($path));

/*End of php*/