几种随机密码生成方法

function create_password($pw_length = 8)
{
    $randpwd = '';
    for ($i = 0; $i < $pw_length; $i++)
    {
        $randpwd .= chr(mt_rand(33, 126));
    }
    return $randpwd;
}

// 调用该函数，传递长度参数$pw_length = 6
echo create_password(6);

function generate_password( $length = 8 ) {
    // 密码字符集，可任意添加你需要的字符
    $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|';

    $password = '';
    for ( $i = 0; $i < $length; $i++ )
    {
        // 这里提供两种字符获取方式
        // 第一种是使用 substr 截取$chars中的任意一位字符；
        // 第二种是取字符数组 $chars 的任意元素
        // $password .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        $password .= $chars[ mt_rand(0, strlen($chars) - 1) ];
    }

    return $password;
}

function create_password($pw_length = 8)
{
    $randpwd = '';
    for ($i = 0; $i < $pw_length; $i++)
    {
        $randpwd .= chr(mt_rand(33, 126));
    }
    return $randpwd;
}

// 调用该函数，传递长度参数$pw_length = 6
echo create_password(6);

function generate_password( $length = 8 ) {
    // 密码字符集，可任意添加你需要的字符
    $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|';

    $password = '';
    for ( $i = 0; $i < $length; $i++ )
    {
        // 这里提供两种字符获取方式
        // 第一种是使用 substr 截取$chars中的任意一位字符；
        // 第二种是取字符数组 $chars 的任意元素
        // $password .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        $password .= $chars[ mt_rand(0, strlen($chars) - 1) ];
    }

    return $password;
}
 

<?php
/*
* Captcha Class base on PHP GD Lib
* @author Design
* @version 1.0
* @copyright js8.in 2010
* @demo
* include('captchaClass.php');
* $captchaDemo=new Captcha();
* $captchaDemo->createImage();
*/
class Captcha{
 //@定义验证码图片高度
 private $height;
 //@定义验证码图片宽度
 private $width;
 //@定义验证码字符个数
 private $textNum;
 //@定义验证码字符内容
 private $textContent;
 //@定义字符颜色
 private $fontColor;
 //@定义随机出的文字颜色
 private $randFontColor;
 //@定义字体大小
 private $fontSize;
 //@定义字体
 private $fontFamily;
 //@定义背景颜色
 private $bgColor;
 //@定义随机出的背景颜色
 private $randBgColor;
 //@定义字符语言
 private $textLang;
 //@定义干扰点数量
 private $noisePoint;
 //@定义干扰线数量
 private $noiseLine;
 //@定义是否扭曲
 private $distortion;
 //@定义扭曲图片源
 private $distortionImage;
 //@定义是否有边框
 private $showBorder;
 //@定义验证码图片源
 private $image;
 
 //@Constructor 构造函数
 public function Captcha(){
 $this->textNum=4;
 $this->fontSize=16;
 $this->fontFamily='c:\windows\fontsSIMYOU.ttf';//设置中文字体，可以改成linux的目录
 $this->textLang='en';
 $this->noisePoint=30;
 $this->noiseLine=3;
 $this->distortion=false;
 $this->showBorder=false;
 }

 
 //@设置图片宽度
 public function setWidth($w){
 $this->width=$w;
 }
 
 //@设置图片高度
 public function setHeight($h){
 $this->height=$h;
 }
 
 //@设置字符个数
 public function setTextNumber($textN){
 $this->textNum=$textN;
 }
 
 //@设置字符颜色
 public function setFontColor($fc){
 $this->fontColor=sscanf($fc,'#%2x%2x%2x');
 }
 
 //@设置字号
 public function setFontSize($n){
 $this->fontSize=$n;
 }
 
 //@设置字体
 public function setFontFamily($ffUrl){
 $this->fontFamily=$ffUrl;
 }
 
 //@设置字符语言
 public function setTextLang($lang){
 $this->textLang=$lang;
 }
 
 //@设置图片背景
 public function setBgColor($bc){
 $this->bgColor=sscanf($bc,'#%2x%2x%2x');
 }
 
 //@设置干扰点数量
 public function setNoisePoint($n){
 $this->noisePoint=$n;
 }
 
 //@设置干扰线数量
 public function setNoiseLine($n){
 $this->noiseLine=$n;
 }
 
 //@设置是否扭曲
 public function setDistortion($b){
 $this->distortion=$b;
 }
 
 //@设置是否显示边框
 public function setShowBorder($border){
 $this->showBorder=$border;
 }
 
 //@初始化验证码图片
 public function initImage(){
 if(empty($this->width)){$this->width=floor($this->fontSize*1.3)*$this->textNum+10;}
 if(empty($this->height)){$this->height=$this->fontSize*2;}
 $this->image=imagecreatetruecolor($this->width,$this->height);
 if(empty($this->bgColor)){
 $this->randBgColor=imagecolorallocate($this->image,mt_rand(100,255),mt_rand(100,255),mt_rand(100,255));
 }else{
 $this->randBgColor=imagecolorallocate($this->image,$this->bgColor[0],$this->bgColor[1],$this->bgColor[2]);
 }
 imagefill($this->image,0,0,$this->randBgColor);
 }
 
 //@产生随机字符
 public function randText($type){
 $string='';
 switch($type){
 case 'en':
 $str='ABCDEFGHJKLMNPQRSTUVWXY3456789';
 for($i=0;$i<$this->textNum;$i++){
 $string=$string.','.$str[mt_rand(0,29)];
 }
 break;
 case 'cn':
 for($i=0;$i<$this->textNum;$i++) {
 $string=$string.','.chr(rand(0xB0,0xCC)).chr(rand(0xA1,0xBB));
 }
 $string=iconv('GB2312','UTF-8',$string); //转换编码到utf8
 break;
 }
 return substr($string,1);
 }
 
 //@输出文字到验证码
 public function createText(){
 $textArray=explode(',',$this->randText($this->textLang));
 $this->textContent=join('',$textArray);
 if(empty($this->fontColor)){
 $this->randFontColor=imagecolorallocate($this->image,mt_rand(0,100),mt_rand(0,100),mt_rand(0,100));
 }else{
 $this->randFontColor=imagecolorallocate($this->image,$this->fontColor[0],$this->fontColor[1],$this->fontColor[2]);
 }
 for($i=0;$i<$this->textNum;$i++){
 $angle=mt_rand(-1,1)*mt_rand(1,20);
 imagettftext($this->image,$this->fontSize,$angle,5+$i*floor($this->fontSize*1.3),floor($this->height*0.75),$this->randFontColor,$this->fontFamily,$textArray[$i]);
 }
 }
 
 //@生成干扰点
 public function createNoisePoint(){
 for($i=0;$i<$this->noisePoint;$i++){
 $pointColor=imagecolorallocate($this->image,mt_rand(0,255),mt_rand(0,255),mt_rand(0,255));
 imagesetpixel($this->image,mt_rand(0,$this->width),mt_rand(0,$this->height),$pointColor);
 }
 
 }
 
 //@产生干扰线
 public function createNoiseLine(){
 for($i=0;$i<$this->noiseLine;$i++) {
 $lineColor=imagecolorallocate($this->image,mt_rand(0,255),mt_rand(0,255),20);
 imageline($this->image,0,mt_rand(0,$this->width),$this->width,mt_rand(0,$this->height),$lineColor);
 }
 }
 
 //@扭曲文字
 public function distortionText(){
 $this->distortionImage=imagecreatetruecolor($this->width,$this->height);
 imagefill($this->distortionImage,0,0,$this->randBgColor);
 for($x=0;$x<$this->width;$x++){
 for($y=0;$y<$this->height;$y++){
 $rgbColor=imagecolorat($this->image,$x,$y);
 imagesetpixel($this->distortionImage,(int)($x+sin($y/$this->height*2*M_PI-M_PI*0.5)*3),$y,$rgbColor);
 }
 }
 $this->image=$this->distortionImage;
 }
 
 //@生成验证码图片
 public function createImage(){
 $this->initImage(); //创建基本图片
 $this->createText(); //输出验证码字符
 if($this->distortion){$this->distortionText();} //扭曲文字
 $this->createNoisePoint(); //产生干扰点
 $this->createNoiseLine(); //产生干扰线
 if($this->showBorder){imagerectangle($this->image,0,0,$this->width-1,$this->height-1,$this->randFontColor);} //添加边框
 imagepng($this->image);
 imagedestroy($this->image);
 if($this->distortion){imagedestroy($this->$distortionImage);}
 return $this->textContent;
 }
 
}
?>使用方法：

<?php
//session_start();
header("Content-type:image/png");
include('captcha5_class.php');
$captcha5=new Captcha();
 
//@设置验证码宽度
//$captcha5->setWidth(200);
 
//@设置验证码高度
//$captcha5->setHeight(50);
 
//@设置字符个数
$captcha5->setTextNumber(5);
 
//@设置字符颜色
//$captcha5->setFontColor('#ff9900');
 
//@设置字号大小
//$captcha5->setFontSize(25);
 
//@设置字体
$captcha5->setFontFamily('c:\windows\fonts\STXINGKA.TTF');
 
//@设置语言
$captcha5->setTextLang('cn');
 
//@设置背景颜色
//$captcha5->setBgColor('#000000');
 
//@设置干扰点数量
//$captcha5->setNoisePoint(600);
 
//@设置干扰线数量
//$captcha5->setNoiseLine(10);
 
//@设置是否扭曲
//$captcha5->setDistortion(true);
 
//@设置是否显示边框
$captcha5->setShowBorder(true);
 
//输出验证码
$code=$captcha5->createImage();
//$_SESSION['captchaCode']['content']=$code;
//$_SESSION['captchaCode']['time']=microtime();
?>

<?php
// 说明：PHP 写的加密函数,支持私人密钥

 
function keyED($txt,$encrypt_key)
{
    $encrypt_key = md5($encrypt_key);
    $ctr=0;
    $tmp = "";
    for ($i=0;$i<strlen($txt);$i++)
    {
        if ($ctr==strlen($encrypt_key)) $ctr=0;
        $tmp.= substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1);
        $ctr++;
    }
    return $tmp;
}  
 
function encrypt($txt,$key)
{
    srand((double)microtime()*1000000);
    $encrypt_key = md5(rand(0,32000));
    $ctr=0;
    $tmp = "";
    for ($i=0;$i<strlen($txt);$i++)
    {
        if ($ctr==strlen($encrypt_key)) $ctr=0;
        $tmp.= substr($encrypt_key,$ctr,1) . (substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1));
        $ctr++;
    }
    return keyED($tmp,$key);
}  
 
function decrypt($txt,$key)
{
    $txt = keyED($txt,$key);
    $tmp = "";
    for ($i=0;$i<strlen($txt);$i++)
    {
        $md5 = substr($txt,$i,1);
        $i++;
        $tmp.= (substr($txt,$i,1) ^ $md5);
    }
    return $tmp;
} 
 
$key = "YITU.org";
$string = "我是加密字符";  
 
// encrypt $string, and store it in $enc_text
$enc_text = encrypt($string,$key);  
 
// decrypt the encrypted text $enc_text, and store it in $dec_text
$dec_text = decrypt($enc_text,$key);  
 
print "加密的 text : $enc_text <Br> ";
print "解密的 text : $dec_text <Br> ";
?>