PHP outputs the session verification code and the picture are not synchronized, and the picture is always a quick step to solve!

PHP outputs the session verification code and the picture are not synchronized, and the picture is always a quick step to solve! PHP outputs the session verification code and the picture are not synchronized, and the picture is always a quick step to solve!

Reply to discussion (solution)

PHP outputs the session verification code and the picture are not synchronized, and the picture is always a quick step.
What does this mean?
Why do you need to repeatedly assign values to $ _ SESSION ["captcha"] in your code?

PHP outputs the session verification code and the picture are not synchronized, and the picture is always a quick step.
What does this mean?
Why do you need to repeatedly assign values to $ _ SESSION ["captcha"] in your code?

Removing the same image is still a step faster than echo.

This problem is very strange. The best way is to separate it.
Try this.
Checkcode. class. php

 Doimage (); * // get verification * $ _ SESSION ['code'] = $ checkcode-> get_code (); session_start (); include '. /checkcode. class. php '; $ checkcode = new checkcode ('C: \ WINDOWS \ Fonts \ ARIAL. ttf'); $ checkcode-> doimage (); $ _ SESSION ['code'] = $ checkcode-> get_code (); */class checkcode {// the verification code width is public $ width = 130; // the verification code height is public $ height = 50; // set the font address private $ font; // set the font color public $ font_color; // Set the random generation factor public $ charset = 'abcdefghkmnprstuvwyza BCDEFGHKLMNPRSTUVWYZ23456789 '; // set the background color public $ background =' # EDF7FF '; // The number of characters generated for the verification code public $ code_len = 4; // The font size public $ font_size = 20; // verification code private $ code; // Image memory private $ img; // private $ x_start where the x axis of the text starts; function _ construct ($ fontpath) {$ this-> font = $ fontpath;}/*** generates a random verification code. */Protected function creat_code () {$ code = ''; $ charset_len = strlen ($ this-> charset)-1; for ($ I = 0; $ I <$ this-> code_len; $ I ++) {$ code. = $ this-> charset [rand (1, $ charset_len)] ;}$ this-> code = $ code ;}/ *** get verification code */public function get_code () {return strtolower ($ this-> code);}/*** generate image */public function doimage () {$ code = $ this-> creat_code (); $ this-> img = imagecreatetruecolor ($ this-> width, $ this-> height); if (! $ This-> font_color) {$ this-> font_color = imagecolorallocate ($ this-> img, rand (0,156), rand (0,156), rand (0,156 ));} else {$ this-> font_color = imagecolorallocate ($ this-> img, hexdec (substr ($ this-> font_color, 1, 2), hexdec (substr ($ this-> font_color, 3, 2), hexdec (substr ($ this-> font_color, 5, 2);} // sets the background color $ background = imagecolorallocate ($ this-> img, hexdec (substr ($ this-> background, 1, 2), hexdec (substr ($ this-> Background, 3, 2), hexdec (substr ($ this-> background, 5, 2); // draw a cabinet and set the background color. Imagefilledrectangle ($ this-> img, 0, $ this-> height, $ this-> width, 0, $ background); $ this-> creat_font (); $ this-> creat_line (); $ this-> output ();}/*** generate text */private function creat_font () {$ x = $ this-> width/$ this-> code_len; for ($ I = 0; $ I <$ this-> code_len; $ I ++) {imagettftext ($ this-> img, $ this-> font_size, rand (-30, 30), $ x * $ I + rand (1.4), $ this-> height, $ this-> font_color, $ this-> font, $ this-> code [$ I]); if ($ I = 0) $ this-> x_start = $ x * $ I + 5;}/*** draw line */private function creat_line () {imagesetthickness ($ this-> img, 3 ); $ xpos = ($ this-> font_size * 2) + rand (-5, 5); $ width = $ this-> width/2.66 + rand (3, 10 ); $ height = $ this-> font_size * 2.14; if (rand (0,100) % 2 = 0) {$ start = rand ); $ ypos = $ this-> height/2-rand (10, 30); $ xpos + = rand (5, 15);} else {$ start = rand (180,246 ); $ ypos = $ this-> height/2 + rand (10, 30);} $ end = $ start + rand (75,110); imagearc ($ this-> img, $ xpos, $ ypos, $ width, $ height, $ start, $ end, $ this-> font_color); if (rand (1,75) % 2 = 0) {$ start = rand (45,111); $ ypos = $ this-> height/2-rand (10, 30); $ xpos + = rand (5, 15 );} else {$ start = rand (200,250); $ ypos = $ this-> height/2 + rand (10, 30);} $ end = $ start + rand (75,100 ); imagearc ($ this-> img, $ this-> width *. 75, $ ypos, $ width, $ height, $ start, $ end, $ this-> font_color);}/*** output image */private function output () {header ("content-type: image/png \ r \ n"); imagepng ($ this-> img); imagedestroy ($ this-> img );}}

Getimg. php

 doimage();$_SESSION['code']=$checkcode->get_code();

Test. php

Submit. php

 ";var_dump($_REQUEST);

Of course

A. php output


The browser requests A. php and outputs the SESSION

When Rendering page A, the image node is found, and captcha. php is requested. the server generates the verification image, and A new SESSION value is generated.

It seems that you have to study hard.

Is it because the browser has installed the debugging plug-in so that the browser loads the page twice?

Is it because the browser has installed the debugging plug-in that the browser will load the page twice, so the verification code is also loaded twice?