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Use PHP to implement login verification code._PHP tutorial
- WBOYOriginal
- 2016-07-13 11:00:091000browse
I saw DEV-CLUB implement verification code login verification a few days ago. It was implemented in PHP last night. Welcome everyone to discuss with me the principle of polygame@163.net
: generate a picture and save the characters displayed in the picture Go to SESSION. When logging in, determine whether the entered verification code is the same as the verification code in SESSION.
Demo address:
http://www.bingdu.net/bbs/
This is the generated verification Code and image files checkNumber.php
session_start();
if($act == "init")
{
Header("Content-type: image /png");
srand(microtime() * 100000);
$login_check_number = strval(rand("1111","9999"));
session_register("login_check_number");
//SESSION is used here to save the check code.
//Of course you can also use COOKIE
//setcookie("login_check_number",$login_check_number);
//Then change the session_start in the first line ()Delete;
//The use of COOKIE is not recommended, because using COOKIE does not allow for secure verification.
$h_img = imagecreate(40,17);
$c_black = ImageColorAllocate($h_img, 0, 0,0);
$c_white = ImageColorAllocate($h_img, 255,255,255);
imageline($h_img, 1, 1, 350, 25, $c_black);
imagearc($h_img, 200, 15 , 20, 20, 35, 190, $c_white);
imagestring($h_img, 5, 2, 1, $login_check_number, $c_white);
ImagePng($h_img);
ImageDestroy($h_img ; checkNumber.php?act=init>
Add the following code to the login verification PHP page (note: there can be no output before adding the code because SESSION is used)
//$number is the verification you entered Code value
include_once("./checkNumber.php");
//Check check code
if($number != $login_check_number || empty($number))
http://www.bkjia.com/PHPjc/631835.html