36 lines
875 B
PHP
36 lines
875 B
PHP
<?php
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session_start();
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header("Content-type: image/png");
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$image = imagecreatetruecolor(85, 25);
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$bgcolor = imagecolorallocate($image, 255, 255, 255);
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imagecolortransparent($image, $bgcolor);
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imagefill($image, 0, 0, $bgcolor);
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$content = "0123456789";
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$captcha = "";
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/* 绘制干扰点 */
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for ($i = 0; $i < 80; $i++) {
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$pointColor = imagecolorallocate($image, rand(100, 255), rand(100, 255), rand(100, 255));
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imagesetpixel($image, rand(0, 85), rand(0, 25), $pointColor);
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}
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/* 绘制验证码 */
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for ($i = 0; $i < 4; $i++) {
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$fontSize = 10;
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$fontColor = imagecolorallocate($image, 155, 155, 155);
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$fontContent = rand(0, 9);
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$captcha .= $fontContent;
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$x = ($i * 85 / 4) + 7;
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$y = rand(3, 8);
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imagestring($image, $fontSize, $x, $y, $fontContent, $fontColor);
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}
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$_SESSION["captcha"] = $captcha;
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imagepng($image);
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imagedestroy($image);
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