PHP Implementation Generation Verification code instance sharing _php instance

image.func.php

<?php require_once (' string.func.php ');  function Verifyimage ($type =1, $length =4, $pixel =0, $line =0, $sess _name= "verify") {session_start (); /* Define length and Width */$width =80; $height =30;/* Create canvas */$image =imagecreatetruecolor ($width, $height); /* This function is used to match the color of the graphic for use by other drawing functions. The parameter image represents the handle of the graph. Parameters red, green, blue are the three primary colors of the color, the value from 0 to 255 .... I hereby define black and white */$white =imagecolorallocate ($image, 255, 255, 255); $black = Imagecolorallocate ($image, 0,0,0); /* This function shades the enclosing rectangular area of the picture. The Parameters x1, y1, and x2, and Y2 are the coordinates of the rectangular diagonal respectively. The parameter col represents the color to be painted */imagefilledrectangle ($image, 1, 1, $width-2, $height-2, $white); The/*buildrandomstring function is used to generate a verification code */$chars =buildrandomstring ($type, $length); /* Pass the verification code to the SESSION to determine if the user input is correct */$_session[$sess _name]= $chars; /* Define Font Library */$fontfiles =array (' Msyh.ttf ', ' Msyhbd.ttf ', ' SIMSUN.TTC ', ' simyou. TTF ', ' Sthupo. TTF ', ' Stkaiti. TTF ', ' Stliti.  TTF ');  /* */FOR ($i =0; $i < $length; $i + +) {$size =mt_rand (14,18) with a loop to write the code one at a)   $angle =mt_rand ( -15,15);  /* The horizontal and vertical coordinates of the verification code */$x =5+ $i * $size;   $y =mt_rand (20,26); $color =imagecolorallocate ($image, Mt_rand (50, Mt_rand (50,200), Mt_rand (50,90)); $fontfile = ".  /font/". $fontfiles [Mt_rand (0,count ($fontfiles)-1)];   $text =substr ($chars, $i, 1); /* This function writes TTF (TrueType Fonts) font text to the picture */Imagettftext ($image, $size, $angle, $x, $y, $color, $fontfile, $text);} if ($pixel) {for ($i =0; $i <50; $i + +) {/* This function can draw a point on the picture. The parameter x, y is the coordinate of the plot point, and the parameter col represents the color of the point */Imagesetpixel ($image, Mt_rand (0, $width-1), Mt_rand (0, $height-1), $black);}} if ($line) {for ($i =0; $i <10; $i + +) {$color =imagecolorallocate ($image, Mt_rand (50,90), Mt_rand (50,200), Mt_rand (  50,90)); /* Draw Segment */Imageline ($image, Mt_rand (0, $width-1), Mt_rand (0, $height-1), Mt_rand (0, $width-1), Mt_rand (0, $height-1), $ color);}} /* Output */header ("Content-type:image/gif") in GIF format,/* Create a GIF graph and output to Web page */imagegif ($image);/* releases memory associated with image */imagedestroy ($ image);}

string.func.php

<?php function  buildrandomstring ($type =1, $length =4) {if ($type ==1) {  /*join functions convert the array to a string: The join () function is an alias for the implode () function */  $chars =join ("", Range (0,9));} ElseIf ($type ==2) {  /*array_merge function Merge array */  $chars =join ("", Array_merge (Range ("A", "Z"), Range ("A", "Z")));} ElseIf ($type ==3) {$chars =join ("", Array_merge (Range ("A", "Z"), Range (  "a", "Z"), Range (0,9)));} if ($length > Strlen ($chars)) {  exit ("insufficient string Length");} /* Scrambled String */$chars =str_shuffle ($chars); return substr ($chars, 0, $length); }?>

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