Backend Development
PHP Problem
What should I do if the php verification code remains unchanged?
What should I do if the php verification code remains unchanged?
Solutions to keep the PHP verification code unchanged: 1. Use the "javascript:ckimg();" method to change a verification code; 2. Use "οnclick="this.src='..." The method is to click to change the picture.
The operating environment of this article: Windows 7 system, PHP version 7.1, DELL G3 computer
What should I do if the php verification code remains unchanged?
php verification code changes without refreshing (replacement)
test.php
<html>
<head>
<script>
function ckimg(){
document.getElementById('img').src="validateCode2.php?"+new Date().getTime();
}
</script>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title></title>
</head>
<body>
<!--第一种方法-->
<a href="javascript:ckimg();" title="更换一张验证码图片"><img src="validateCode2.php" id="img" alt="看不清，请换一张" /></a> <a href="javascript:ckimg();" title="更换一张验证码图片">看不清，请换一张</a>
<!--第二种方法-->
<img src="validateCode2.php" alt="看不清，点击换图片" id="img" οnclick="this.src='validateCode2.php?'+new Date().getTime();" style='cursor:pointer;'>
</body>
</html>Production verification The code class contains some parameters for verification code generation, such as: size, color, symbol type for displaying verification code
validateCode2.php
<?php
session_start();
class Authnum {
//图片对象、宽度、高度、验证码长度
private $im;
private $im_width;
private $im_height;
private $len;
//随机字符串、y轴坐标值、随机颜色
private $randnum;
private $y;
private $randcolor;
//背景色的红绿蓝，默认是浅灰色
public $red=238;
public $green=238;
public $blue=238;
/**
* 可选设置：验证码类型、干扰点、干扰线、Y轴随机
* 设为 false 表示不启用
**/
//默认是大小写数字混合型，1 2 3 分别表示 小写、大写、数字型
public $ext_num_type='';
public $ext_pixel = false; //干扰点
public $ext_line = false; //干扰线
public $ext_rand_y= true; //Y轴随机
function __construct ($len=4,$im_width='',$im_height=25) {
// 验证码长度、图片宽度、高度是实例化类时必需的数据
$this->len = $len; $im_width = $len * 15;
$this->im_width = $im_width;
$this->im_height= $im_height;
$this->im = imagecreate($im_width,$im_height);
}
// 设置图片背景颜色，默认是浅灰色背景
function set_bgcolor () {
imagecolorallocate($this->im,$this->red,$this->green,$this->blue);
}
// 获得任意位数的随机码
function get_randnum () {
$an1 = 'abcdefghijklmnopqrstuvwxyz';
$an2 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$an3 = '0123456789';
if ($this->ext_num_type == '') $str = $an1.$an2.$an3;
if ($this->ext_num_type == 1) $str = $an1;
if ($this->ext_num_type == 2) $str = $an2;
if ($this->ext_num_type == 3) $str = $an3;
for ($i = 0; $i < $this->len; $i++) {
$start = rand(1,strlen($str) - 1);
$randnum .= substr($str,$start,1);
}
$this->randnum = $randnum;
$_SESSION[an] = $this->randnum;
}
// 获得验证码图片Y轴
function get_y () {
if ($this->ext_rand_y) $this->y = rand(5, $this->im_height/5);
else $this->y = $this->im_height / 4 ;
}
// 获得随机色
function get_randcolor () {
$this->randcolor = imagecolorallocate($this->im,rand(0,100),rand(0,150),rand(0,200));
}
// 添加干扰点
function set_ext_pixel () {
if ($this->ext_pixel) {
for($i = 0; $i < 100; $i++){
$this->get_randcolor();
imagesetpixel($this->im, rand()%100, rand()%100, $this->randcolor);
}
}
}
// 添加干扰线
function set_ext_line () {
if ($this->ext_line) {
for($j = 0; $j < 2; $j++){
$rand_x = rand(2, $this->im_width);
$rand_y = rand(2, $this->im_height);
$rand_x2 = rand(2, $this->im_width);
$rand_y2 = rand(2, $this->im_height);
$this->get_randcolor();
imageline($this->im, $rand_x, $rand_y, $rand_x2, $rand_y2, $this->randcolor);
}
}
}
/**创建验证码图像：
* 建立画布（__construct函数）
* 设置画布背景（$this->set_bgcolor();）
* 获取随机字符串（$this->get_randnum ();）
* 文字写到图片上（imagestring函数）
* 添加干扰点/线（$this->set_ext_line(); $this->set_ext_pixel();）
* 输出图片
**/
function create () {
$this->set_bgcolor();
$this->get_randnum ();
for($i = 0; $i < $this->len; $i++){
$font = rand(4,6);
$x = $i/$this->len * $this->im_width + rand(1, $this->len);
$this->get_y();
$this->get_randcolor();
imagestring($this->im, $font, $x, $this->y, substr($this->randnum, $i ,1), $this->randcolor);
}
$this->set_ext_line();
$this->set_ext_pixel();
header("content-type:image/png");
imagepng($this->im);
imagedestroy($this->im); //释放图像资源
}
}//end class
/**使用验证码类的方法：
* $an = new Authnum(验证码长度,图片宽度,图片高度);
* 实例化时不带参数则默认是四位的60*25尺寸的常规验证码图片
* 表单页面检测验证码的方法，对比 $_SESSION[an] 是否等于 $_POST[验证码文本框ID]
* 可选配置：
* 1.验证码类型：$an->ext_num_type=1; 值为1是小写类型，2是大写类型，3是数字类型
* 2.干扰点：$an->ext_pixel = false; 值为false表示不添加干扰点
* 3.干扰线：$an->ext_line = false; 值为false表示不添加干扰线
* 4.Y轴随机：$an->ext_rand_y = false; 值为false表示不支持图片Y轴随机
* 5.图片背景：改变 $red $green $blue 三个成员变量的值即可
**/
$an = new Authnum();
$an->ext_num_type='';
$an->ext_pixel = true; //干扰点
$an->ext_line = false; //干扰线
$an->ext_rand_y= true; //Y轴随机
$an->green = 238;
$an->create();
?>Recommended study: "PHP video tutorial》
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