php隨機驗證碼 php產生隨機驗證碼(圖文)

for($i = 0; $i<6; $i++){ $_md_color = imagecolorallocate($_img,mt_rand(0, 255),mt_rand(0, 255), mt_rand(0, 255)); imageline($_img, mt_rand(0, 75), mt_rand(0, 75), mt_rand(0, 75), mt_rand(0, 75),$_md_color); } //隨機雪花 for($i = 0; $i<100;$i++){ $_md_color = imagecolorallocate($_img, mt_rand(200, 255), mt_rand(200, 255), mt_rand(200, 255)); imagestring($_img, 1, mt_rand(1, $_width), mt_rand(1, $_height), '*', $_md_color); } //黑色邊框 $_black = imagecolorallocate($_img, 0, 0, 0); imagerectangle($_img, 0, 0, $_width-1, $_height-1, $_black); //輸出驗證碼 for($i = 0;$i $_mt_color = imagecolorallocate($_img, mt_rand(0, 100), mt_rand(0, 150), mt_rand(0, 200)); imagestring($_img, mt_rand(3, 5), $i*$_width/4+mt_rand(1, 10), mt_rand(1, $_height/2), $_SESSION['code'][$i],$_mt_color); } header('Content-Type:image/png'); imagepng($_img); //銷毀 imagedestroy($_img); ?> 複製代碼

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