- <?php
- session_start();
- // main
- $vcodes = '';
- //generate Number 4
- srand((double) microtime() * 1000000);
- for ($i = 0; $i < 4; $i++) {
- $vcodes .= rand(1, 9);
- }
- $_SESSION['eifr_checkvcode'] = $vcodes;
- if (function_exists('imagecreate')) {
- //generate picture validation code
- Header("Content-type: image/PNG");
- $img = imagecreate(44, 18);
- $bg = ImageColorAllocate($img, 245, 245, 245);
- imagefill($img, 0, 0, $bg); //background
- //generate Number 4
- for ($i = 0; $i < 4; $i++) {
- $font = ImageColorAllocate($img, rand(100, 255), rand(0, 100), rand(100, 255));
- $vnum = substr($vcodes, $i, 1);
- imagestring($img, 5, 2 + $i * 10, 1, $vnum, $font);
- }
- //add interference
- for ($i = 0; $i < 100; $i++) {
- $randcolor = ImageColorallocate($img, rand(0, 255), rand(0, 255), rand(0, 255));
- imagesetpixel($img, rand() % 70, rand() % 30, $randcolor);
- }
- ImagePNG($img);
- ImageDestroy($img);
- }
- ?>
来源: http://www.phpxs.com/code/1003352/