<?php

//require_once "include.php";

header("content-type:text/html;charset=utf-8");

date_default_timezone_set("PRC");

session_start();

/**

?* 生成驗證碼

?* @param int $type

?* @param int $length

?* @return string

?*/

function buildRandomString($type=1,$length=4){

if ($type == 1) {

$chars = join ( "", range ( 0, 9 ) );

} elseif ($type == 2) {

$chars = join ( "", array_merge ( range ( "a", "z" ), range ( "A", "Z" ) ) );

} elseif ($type == 3) {

$chars = join ( "", array_merge ( range ( "a", "z" ), range ( "A", "Z" ), range ( 0, 9 ) ) );

}

if ($length > strlen ( $chars )) {

exit ( "字符串長度不夠" );

}

$chars = str_shuffle ( $chars );

return substr ( $chars, 0, $length );

}

//通過GD庫做驗證碼

function verifyImage($type=1,$length=4,$pixel=0,$line=0,$sess_name = "verify"){

//session_start();

//創建畫布

$width = 80;

$height = 28;

$image = imagecreatetruecolor ( $width, $height );

$white = imagecolorallocate ( $image, 255, 255, 255 );

$black = imagecolorallocate ( $image, 0, 0, 0 );

//用填充矩形填充畫布

imagefilledrectangle ( $image, 1, 1, $width - 2, $height - 2, $white );

$chars = buildRandomString ( $type, $length );

$_SESSION [$sess_name] = $chars;

//$fontfiles = array ("MSYH.TTF", "MSYHBD.TTF", "SIMLI.TTF", "SIMSUN.TTC", "SIMYOU.TTF", "STZHONGS.TTF" );

$fontfiles = array ("comic.ttf" );

//由于字體文件比較大，就只保留一個字體，如果有需要的同學可以自己添加字體，字體在你的電腦中的fonts文件夾里有，直接運行輸入fonts就能看到相應字體

for($i = 0; $i < $length; $i ++) {

$size = mt_rand ( 14, 18 );

$angle = mt_rand ( - 15, 15 );

$x = 5 + $i * $size;

$y = mt_rand ( 20, 26 );

$fontfile = "./fonts/" . $fontfiles [mt_rand ( 0, count ( $fontfiles ) - 1 )];

$color = imagecolorallocate ( $image, mt_rand ( 50, 90 ), mt_rand ( 80, 200 ), mt_rand ( 90, 180 ) );

$text = substr ( $chars, $i, 1 );

imagettftext ( $image, $size, $angle, $x, $y, $color, $fontfile, $text );

}

if ($pixel) {

for($i = 0; $i < 50; $i ++) {

imagesetpixel ( $image, mt_rand ( 0, $width - 1 ), mt_rand ( 0, $height - 1 ), $black );

}

}

if ($line) {

for($i = 1; $i < $line; $i ++) {

$color = imagecolorallocate ( $image, mt_rand ( 50, 90 ), mt_rand ( 80, 200 ), mt_rand ( 90, 180 ) );

imageline ( $image, mt_rand ( 0, $width - 1 ), mt_rand ( 0, $height - 1 ), mt_rand ( 0, $width - 1 ), mt_rand ( 0, $height - 1 ), $color );

}

}

header ( "content-type:image/gif" );

imagegif ( $image );

imagedestroy ( $image );

}

verifyImage();