第六节 ThinkPHP 验证码
最后更新于：2022-04-02 01:47:06
>[success] # ThinkPHP 验证码
* 验证码可以防止机器人的恶意请求(恶意表单提交、破解密码、刷票、论坛灌水......)
>[info] # 源码下载
- Tip：公众号回复【023】获取源代码
>[success] # 原生PHP 实现验证码
* 字体文件下载msjh.ttf 链接：https://pan.baidu.com/s/1jHLpYku 密码：el2k
```php
font = 'msjh.ttf';//注意字体路径要写对，否则显示不了图片
}
//生成验证码
private function createCode()
{
$len = strlen($this->charset) - 1;
for ($i = 0; $i < $this->codelen; $i++) {
$this->code .= $this->charset[mt_rand(0, $len)];
}
}
//生成背景
private function createBg()
{
$this->img = imagecreatetruecolor($this->width, $this->height);
//imagecreatetruecolor — 新建一个真彩色图像
$color = imagecolorallocate($this->img, mt_rand(157, 255), mt_rand(157, 255), mt_rand(157, 255));
//imagecolorallocate — 为一幅图像分配颜色
imagefilledrectangle($this->img, 0, $this->height, $this->width, 0, $color);
}
//生成文字
private function createFont()
{
//每个字符的平均宽度
$x = $this->width / $this->codelen;
for ($i = 0; $i < $this->codelen; $i++) {
//字体的颜色
$this->fontColor = imagecolorallocate($this->img, mt_rand(0, 156), mt_rand(0, 156), mt_rand(0, 156));
imagettftext($this->img, $this->fontSize, mt_rand(-10, 10), $i * $x + mt_rand(1, 3), $this->height / 1.3, $this->fontColor, $this->font, $this->code[$i]);
//imagestring($this->img,5,$i*$x+mt_rand(1,5),5,$this->code[$i],$this->fontColor);
}
}
//生成线条、雪花
private function createDisturb()
{
for ($i = 0; $i < 6; $i++) {
$color = imagecolorallocate($this->img, mt_rand(0, 156), mt_rand(0, 156), mt_rand(0, 156));
imageline($this->img, mt_rand(0, $this->width), mt_rand(0, $this->width), mt_rand(0, $this->width), mt_rand(0, $this->width), $color);
//imageline() 用 color 颜色在图像 image 中从坐标 x1，y1 到 x2，y2（图像左上角为 0, 0）画一条线段。
}
for ($i = 0; $i < 100; $i++) {
$color = imagecolorallocate($this->img, mt_rand(200, 255), mt_rand(200, 255), mt_rand(200, 255));
imagestring($this->img, mt_rand(1, 5), mt_rand(0, $this->width), mt_rand(0, $this->height), '*', $color);
//imagestring — 水平地画一行字符串
}
}
//输出
private function outPut()
{
header("Content-Type:image/png");
imagepng($this->img);
imagedestroy($this->img);
}
//显示验证码
public function showCode()
{
$this->createBg();
echo $this->code;
$this->createCode();
//$_SESSION['code'] = $this->getCode();
$this->createDisturb();
$this->createFont();
$this->outPut();
}
//获取验证码
public function getCode()
{
return strtolower($this->code);
}
}
$code = new VerificationCode();
$code->showCode();
```
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