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Generate verification code to randomly interfere with PHP implementation

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WBOYOriginal
2016-07-25 08:46:03969browse
  1. session_start ();
  2. header ( 'Content-type: image/png' );
  3. //Create image
  4. $im = imagecreate($x=130,$y=45 );
  5. $bg = imagecolorallocate($im,rand(50,200),rand(0,155),rand(0,155)); //The first call to imagecolorallocate() will fill the background color of the palette-based image
  6. $fontColor = imageColorAllocate ($im, 255, 255, 255); //Font color
  7. $fontstyle = 'rock.ttf'; //Font style, this can be found in the c:windowsFonts folder, I put it in and authcode. php file, you can replace other font styles here
  8. //Generate random characters
  9. for($i = 0; $i < 4; $i ++) {
  10. $randAsciiNumArray = array (rand(48,57 ),rand(65,90));
  11. $randAsciiNum = $randAsciiNumArray [rand ( 0, 1 )];
  12. $randStr = chr ( $randAsciiNum );
  13. imagettftext($im,30,rand(0,20)- rand(0,25),5+$i*30,rand(30,35),$fontColor,$fontstyle,$randStr);
  14. $authcode .= $randStr;
  15. }
  16. $_SESSION['authcode'] = $randFourStr;//Compare the user with the verification code entered by the user
  17. //Interference line
  18. for ($i=0;$i<8;$i++){
  19. $lineColor = imagecolorallocate($im,rand(0,255) ,rand(0,255),rand(0,255));
  20. imageline ($im,rand(0,$x),0,rand(0,$x),$y,$lineColor);
  21. }
  22. //Interference Click
  23. for ($i=0;$i<250;$i++){
  24. imagesetpixel($im,rand(0,$x),rand(0,$y),$fontColor);
  25. }
  26. imagepng($ im);
  27. imagedestroy($im);
  28. ?>
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Verification code, php


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