验证码

add_action("wpcf7_init", function(){
	if( function_exists( 'wpcf7_add_form_tag' ) ) {
		wpcf7_add_form_tag("validcode", "juxin_validcode_handler", true);
		wpcf7_add_form_tag("validcode*", "juxin_validcode_handler", true);
	}

});

function juxin_validcode_handler($tag){
	$tag = new WPCF7_FormTag( $tag );
	if( empty($tag->name) ) return '';
	$atts = array();
	if ( $tag->is_required() ) {
		$atts['aria-required'] = 'true';
	}
	$validation_error = wpcf7_get_validation_error( $tag->name );
	$atts['aria-invalid'] = $validation_error ? 'true' : 'false';
	$value = (string) reset( $tag->values );
	if ( $tag->has_option( 'placeholder' )
		or $tag->has_option( 'watermark' ) ) {
		$atts['placeholder'] = $value;
		$value = '';
	}
	$atts['name'] = $tag->name;
	$atts['type'] = "text";
	$atts['bind'] = $tag->get_option('bind', 'class', true);
	$atts = wpcf7_format_atts( $atts );
	$html = sprintf(
		'<span class="wpcf7-form-control-wrap validcode %1$s"><input autocomplete="off" id="validcode_input" %2$s />%3$s</span><div id="validcode_image"><img src="/?get_validatecode=get_validatecode" /></div>',
		sanitize_html_class( $tag->name ), $atts, $validation_error
	);
	$html.= '
	<script>
		jQuery(function($){
			$("#validcode_input").focus(function(){
				$("#validcode_image img").click()
			})
			$("#validcode_image img").click(function(){
				$(this).attr("src","/?get_validatecode=get_validatecode&time='.time().'")
			})
		});
	</script>
	';
	return $html;
}
add_filter( 'wpcf7_validate_validcode', "juxin_validcode_validation_filter", 10, 2 );
add_filter( 'wpcf7_validate_validcode*', "juxin_validcode_validation_filter", 10, 2 );
function juxin_validcode_validation_filter( $result, $tag ) {
	$name = $tag->name;
	$value = isset( $_POST[$name] )
		? trim( wp_unslash( strtr( (string) $_POST[$name], "\n", " " ) ) )
		: '';
	if ( $value === '' ) {
		$result->invalidate( $tag, "请输入验证码！" );
	} else {
		if (strcmp($value,$_SESSION['custom_validcode']) <> 0 ) {
			$result->invalidate( $tag, '验证码错误' );
		}
	}

	return $result;
}



add_action('init', function(){
session_start();
	if( $_GET['get_validatecode'] == 'get_validatecode') {
		$ValidateCode = new ValidateCode();
		$ValidateCode->doimg();
		$_SESSION['custom_validcode'] = $ValidateCode->getCode();
		die;
	} else if ($_GET['eeee'] == 'eeee') {
		echo $_SESSION['custom_validcode'];
		die;
	}
});

//验证码类
class ValidateCode {
	private $charset = '*+?abcdefghkmnprstuvwxyzABCDEFGHKMNPRSTUVWXYZ23456789';	//随机因子
	private $code;				//验证码
	private $codelen = 6;		//验证码长度
	private $width = 200;		//宽度
	private $height = 50;		//高度
	private $img;				//图形资源句柄
	private $font;				//指定的字体
	private $fontsize = 20;		//指定字体大小
	private $fontcolor;			//指定字体颜色


	//构造方法初始化
	public function __construct() {
		$this->font = WP_CONTENT_DIR.'/uploads/Fonts/elephant.ttf';
	}


	//生成随机码
	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);
		$color = imagecolorallocate($this->img, mt_rand(0,255), mt_rand(0,255), mt_rand(0,255));
		imagefilledrectangle($this->img,0,$this->height,$this->width,0,$color);
	}


	//生成文字
	private function createFont() {
		$_x = $this->width / $this->codelen;
		for ($i=0;$i<$this->codelen;$i++) {
			$this->fontcolor = imagecolorallocate($this->img,mt_rand(0,100),mt_rand(0,100),mt_rand(0,100));
			imagettftext($this->img,$this->fontsize,mt_rand(-30,30),$_x*$i+mt_rand(1,5),$this->height / 1.4,$this->fontcolor,$this->font,$this->code[$i]);
		}
	}


	//生成线条、雪花
	private function createLine() {
		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,$this->height),mt_rand(0,$this->width),mt_rand(0,$this->height),$color);
		}
		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);
		}
	}


	//输出
	private function outPut() {
		header('Content-type:image/png');
		imagepng($this->img);
		imagedestroy($this->img);
	}


	//对外生成
	public function doimg() {
		$this->createBg();
		$this->createCode();
		$this->createLine();
		$this->createFont();
		$this->outPut();
	}


	//获取验证码
	public function getCode() {
		// return strtolower($this->code);
		return $this->code;
	}
}