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(); ?>
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