php生成验证码实现代码
一款php生成验证码实现代码,自定义了session的目录,这样就不是php.ini里默认的session文件保存路径了,如下面session_save_path,可重新定义目录.
session_save_path,可重新定义目录,php生成验证码实现代码如下:
- $sesssavepath = dirname(__file__)."/../data/sessions/";
- if(is_writeable($sesssavepath) && is_readable($sesssavepath)){ session_save_path($sesssavepath); }
- session_start();
- $vstr = '';
- for($i=0; $i<4; $i++) $vstr .= chr(mt_rand(65,90));
- if(function_exists("imagecreate")){
- $ntime = time();
- if(emptyempty($_session['verifycode_last']) || emptyempty($_session['verifycode']) || ($ntime - $_session['verifycode_last'] > 5)){
- $_session['verifycode'] = strtolower($vstr);
- $_session['verifycode_last'] = $ntime;
- }
- $vstr = $_session['verifycode'];
- $vstrlen = strlen($vstr);
- $img = imagecreate(50,20);
- imagecolorallocate($img, 255,255,255);
- $line1 = imagecolorallocate($img,240,220,180);
- $line2 = imagecolorallocate($img,250,250,170);
- for($j=3;$j<=16;$j=$j+3){
- imageline($img,2,$j,48,$j,$line1);
- }
- for($j=2;$j<52;$j=$j+(mt_rand(3,6))){
- imageline($img,$j,2,$j-6,18,$line2);
- }
- $bordercolor = imagecolorallocate($img, 0x99,0x99,0x99);
- imagerectangle($img, 0, 0, 49, 19, $bordercolor);
- $fontcolor = imagecolorallocate($img, 48,61,50);
- for($i=0;$i<$vstrlen;$i++){
- $bc = mt_rand(0,1);
- $vstr[$i] = strtoupper($vstr[$i]);
- imagestring($img, 5, $i*10+6, mt_rand(2,4), $vstr[$i], $fontcolor);
- }
- header("pragma:no-cachern");
- header("cache-control:no-cachern");
- header("expires:0rn");
- if(function_exists("imagejpeg")){
- header("content-type:image/jpegrn");
- imagejpeg($img);
- }else{
- header("content-type:image/pngrn");
- imagepng($img);
- }
- imagedestroy($img);
- exit();//开源代码phpfensi.com
- }