Php verification code

Php verification code how to kneel down and ask the master to add my qq7798000029, randomly select a number or letter and then display it in the form of an image. 1. assume that you are a login. php page: & lt ;? Php & nbsp; include (& quot; conn. php & quot;) how to get the php verification code
Click here to add my qq7798000029

------ Solution --------------------
Just randomly select numbers or letters and display them as images.
------ Solution --------------------
1. assume that you have a login. php page: under this page,
Include ("conn. php"); // Connect to Mysql.
Session_start ();
Echo $ _ SESSION [check_pic];

If ($ _ POST ){
$ Code = $ _ POST [code];
If ($ code! = $ _ SESSION [check_pic])
Echo "script" alert ('The verification code is incorrect! '); Location. href = 'login. php'; script ";

}

?>


2. src = 'Inc/vCode. php? Tm = '+ Math. inc/vCode in random. php refers to the inc folder in the current directory, which contains a vCode. php, you create a new vCode. php, the code is as follows, you can paste it:
/*
* Put a font. ttc font in the directory.
$ Num characters
$ Size character size
Random color
*/
// VCode ********
Function vCode ($ num = 4, $ size = 20, $ width = 0, $ height = 0 ){
Session_start ();
! $ Width & amp; $ width = $ num * $ size * 4/5 + 5;
! $ Height & $ height = $ size + 10;
// Remove 0 1 O l and so on
$ Str= "23456789 abcdefghijkmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVW ";
$ Code = '';
For ($ I = 0; $ I <$ num; $ I ++ ){
$ Code. = $ str [mt_rand (0, strlen ($ str)-1)];
}
$ _ SESSION [check_pic] = $ code;
// Draw an image
$ Im = imagecreatetruecolor ($ width, $ height );
// Define the color to be used
$ Back_color = imagecolorallocate ($ im, 235,236,237 );
$ Boer_color = imagecolorallocate ($ im, 118,151,199 );
$ Text_color = imagecolorallocate ($ im, mt_rand (0,200), mt_rand (0,120), mt_rand (0,120 ));

// Draw the background
Imagefilledrectangle ($ im, 0, 0, $ width, $ height, $ back_color );
// Draw a border
Imagerectangle ($ im, 0, 0, $ width-1, $ height-1, $ boer_color );
// Draw interference lines
For ($ I = 0; $ I <5; $ I ++ ){
$ Font_color = imagecolorallocate ($ im, mt_rand (0,255), mt_rand (0,255), mt_rand (0,255 ));
Imagearc ($ im, mt_rand (-$ width, $ width), mt_rand (-$ height, $ height), mt_rand (30, $ width * 2), mt_rand (20, $ height * 2), mt_rand (0,360), mt_rand (0,360), $ font_color );
}
// Draw interference points
For ($ I = 0; $ I <50; $ I ++ ){
$ Font_color = imagecolorallocate ($ im, mt_rand (0,255), mt_rand (0,255), mt_rand (0,255 ));
Imagesetpixel ($ im, mt_rand (0, $ width), mt_rand (0, $ height), $ font_color );
}
// Draw the verification code
Imagefttext ($ im, $ size, 0, 5, $ size + 3, $ text_color, 'simkai. ttf', $ code );
Header ("Cache-Control: max-age = 1, s-maxage = 1, no-cache, must-revalidate ");
Header ("Content-type: image/png ");
Imagepng ($ im );
Imagedestroy ($ im );
}
VCode (4, 20 );

// 4 characters, 20 characters
// Call method:
?>