PHP programming every day must learn the verification code, PHP programming Verification Code _php tutorial

PHP programming every day must learn the verification code, PHP programming verification code

This article for you to share the PHP picture Verification Code Implementation code, share to everyone for reference, the specific content as follows

1. Verification Code Image generation
captcha.php

1. Generate 100*30 size picture, default to Black $image = Imagecreatetruecolor (100,30);//Create white Basemap $bgcolor = Imagecolorallocate ($image, 255,255,255);//Fill black imagefill with white ($image, 0,0, $bgcolor)//2. Random display of numbers or letters $captch_code = ""; for ($i =0; $i <4; $i + +) {$ fontsize=6; $fontcolor =imagecolorallocate ($image, Rand (0,120), Rand (0,120), Rand (0,120)); $data = "abcdefghijkmnpqrstuvwxy3456789"; $fontcontent =substr ($data, Rand (0,strlen ($DATA)), 1); $captch _code. = $fontcontent; $x = ($i *100/4) +rand (5,10); $y = rand (5,10); Imagestring ($image, $fontsize, $x, $y, $fontcontent, $fontcolor);} $_session["Authcode"] = $captch _CODE;//3. Add interference/interference points for ($i =0; $i <100; $i + +) {$pointcolor =imagecolorallocate ($image , Rand (50,200), Rand (50,200), Rand (50,200)); Imagesetpixel ($image, Rand (1,99), Rand (1,29), $pointcolor);} Interference line for ($i =0; $i <2; $i + +) {$linecolor =imagecolorallocate ($image, Rand (80,220), Rand (80,220), Rand (80,220)); Imageline ($image, Rand (1,99), Rand (1,29), Rand (1,99), Rand (1,29), $linecolor);} Header ("Content-type:image/png"); Imagepng ($image);

2. Page Implementation Verification Code function
form.php

<?phpif (Isset ($_post["Authcode"])) {session_start (); if (Strtolower ($_post["Authcode"]) ==$_session["Authcode"] {  echo "OK";} else{  echo "NO";}}? > 
 
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The above is the entire content of this article, to help you easily implement PHP image verification code.

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http://www.bkjia.com/PHPjc/1106131.html www.bkjia.com true http://www.bkjia.com/PHPjc/1106131.html techarticle PHP Programming every day must learn the verification code, PHP programming Verification code This article for you to share the PHP image verification Code Implementation code, share to everyone for your reference, the specific content is as follows 1. captcha Image ...

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