Get the QR code of wechat applet with parameters - and share the source code of modifying the QR code logo

logic analysis ：
1. First, prepare the applet APPID and SECRET, Available on wechat official account . And prepare the parameters you want to bring into the QR code
2.logo Upload ： Receive the uploaded logo picture , First draw the picture into a circle , Then get the QR code , hold logo The picture is embedded on the QR code .

See the code demonstration : The important way to use is to look at the table of contents

Method of obtaining QR code ：

public function recreateOp(){
    
		if (request()->ispost() && request()->isAjax()) {
    
            $logo = request()->file('file'); //  The uploaded logo
			$width = input('width'); //  Width 
			$shape = input('shape'); //  QR code shape 
			if($width < 280 || $width > 1280){
    
				return json_encode(['status'=>ERROR,'msg'=>' Wrong width ']);
			}
			if($shape != 1 && $shape != 2){
    
				return json_encode(['status' => ERROR, 'msg' => ' Wrong type ']);
			}

			$appid = " Your own appid Find... In wechat official account ";
			$appsecret = " Yours appsecret Find... In wechat official account ";
			$usertoken = " You need to bring in the parameters in the QR code ";
			if (!$usertoken) {
    
				return json_encode(['status' => ERROR, 'msg' => ' The information is wrong ']);
			}
            $Applet = new Applet(); // Applet()  class 
            if (!empty($logo)) {
    
                $filename = uniqid('qrlogo_img_' . false);
                $retImg = upload_files($logo, USER_QRLOGO_PATH, $filename); //  Upload files 
                if ($retImg['status'] == 9) {
    
                    $head_img = USER_QRLOGO_PATH.$retImg['msg'];
                } else {
    
                    return json_encode(['status' => 'error', 'msg' => $retImg['msg']]);
                }
                $logo = $Applet->yuanImg($head_img); //  Upload logo Use PHP Self contained GD The library is drawn in a circle 
                @unlink($head_img); //  Delete the uploaded logo picture 
            }

            $Applet->creatCode($appid, $appsecret, $usertoken, $this->userinfo['uid'], $shape, $width,$logo);
			return json_encode(['status' => SUCCESS, 'msg' => ' QR code has been regenerated ','url'=>url('jieru')]);
		}
	}

Applet() class ：

/* *  Generate an applet to access the exclusive QR code  * $appid  Applet appid * $appsecret  Applet appsecret * $usertoken  Access code  * $shape  QR code shape ：1- Chrysanthemum type ,2- square  * $width  QR code width  */ 
	public function creatCode($appid, $appsecret, $usertoken, $uid, $shape = 1, $width=280,$logo = '') {
    
		// obtain access_token
		$access_token = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=$appid&secret=$appsecret";
		$json = $this->httpRequest($access_token);
		$token = json_decode($json, true);
		$token = $token['access_token'];
		//  Build request QR code parameters 
		switch ($shape) {
    
			case 1:	// Chrysanthemum type 
				$qcode = "https://api.weixin.qq.com/wxa/getwxacode?access_token=$token"; // Chrysanthemum QR code 
				break;
			
			default:	// Square type 
				$qcode = "https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode?access_token=$token"; //  Square QR code 
				break;
		}
		//  Send the parameter combination in the QR code to the wechat interface 
		$param = json_encode(array("path" => "pages/login/login?tongxingma=$usertoken", "width" => $width));
		// $res  Is the acquired QR code , You can save the QR code to the database 
		$res = $this->httpRequest($qcode, $param, "POST"); //  send out http Request for a QR code with parameters 
        if (!empty($logo)) {
    
            $res = $this->qrcodeWithLogo($res,$logo,$shape); //  Mosaic the picture in the middle of the QR code 
        }

		// Save QR code picture 
		$file_name = time(). createStr(6) . ".png"; //  Generate QR code picture name 
		$path = ROOT_PATH . 'public/uploads/appLetCode/'. $usertoken.'/'; //  Save the path 
		$upload = $path . $file_name;
		if (!file_exists($path)) mkdir($path, 0777, true); 
		file_put_contents($upload, $res);
		// Save data to database 
		$olddata = model('Applet')->where(['uid' => $uid])->field('numid,name')->find();
		if(!$olddata){
    	// The new data 
			$data = [
				'uid' => $uid,
				'name' => $file_name,
				'width' => $width,
				'shape' => $shape,
				'addtime' => time(),
				'status' => 9,
			];
			model('Applet')->allowField(true)->save($data);
		}else{
    	// Update data 
			if (file_exists($path . $olddata['name'])) {
    
				@unlink($path . $olddata['name']);
			}
			$data = [
				'numid' => $olddata['numid'],
				'name' => $file_name,
				'width' => $width,
				'shape' => $shape,
				'addtime' => time(),
				'status' => 9,
			];
			model('Applet')->allowField(true)->isUpdate(true)->save($data);
		}
		return [
			// Turn into base64
			'base64_image' =>  	"data:image/jpeg;base64," . base64_encode($res), 
			'upload'       => 	$file_name,
		];
	}

http Request method ：

// Send the request to wechat server for QR code 
	private function httpRequest($url, $data = '', $method = 'GET'){
    
		$curl = curl_init();
		curl_setopt($curl, CURLOPT_URL, $url);
		curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 0);
		curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 0);
		curl_setopt($curl, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
		curl_setopt($curl, CURLOPT_FOLLOWLOCATION, 1);
		curl_setopt($curl, CURLOPT_AUTOREFERER, 1);
		if ($method == 'POST') {
    
			curl_setopt($curl, CURLOPT_POST, 1);
			if ($data != '') {
    
				curl_setopt($curl, CURLOPT_POSTFIELDS, $data);
			}
		}

		curl_setopt($curl, CURLOPT_TIMEOUT, 30);
		curl_setopt($curl, CURLOPT_HEADER, 0);
		curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
		$result = curl_exec($curl);
		curl_close($curl);
		return $result;
	}

Cut Uploaded logo The picture is a circular method ：

  /** *  Cut the picture into a circle  * @param $picture  Picture data stream   such as file_get_contents(imageurl) Return to the East  * @return  Picture data stream  */
    public function yuanImg($picture) {
    
        $picture = file_get_contents($picture);
        $src_img = imagecreatefromstring($picture);
        $w = imagesx($src_img);
        $h = imagesy($src_img);
        $w = min($w, $h);
        $h = $w;
        $img = imagecreatetruecolor($w, $h);
        // This sentence must have 
        imagesavealpha($img, true);
        // Pick a completely transparent color , Last parameter 127 For full transparency 
        $bg = imagecolorallocatealpha($img, 255, 255, 255, 127);
        imagefill($img, 0, 0, $bg);
        $r = $w / 2; // Circle radius 
        $y_x = $r; // center of a circle X coordinate 
        $y_y = $r; // center of a circle Y coordinate 
        for ($x = 0; $x < $w; $x++) {
    
            for ($y = 0; $y < $h; $y++) {
    
                $rgbColor = imagecolorat($src_img, $x, $y);
                if (((($x - $r) * ($x - $r) + ($y - $r) * ($y - $r)) < ($r * $r))) {
    
                    imagesetpixel($img, $x, $y, $rgbColor);
                }
            }
        }
        /** *  If you want to output pictures directly , It should be set first header.header("Content-Type: image/png; charset=utf-8"); *  And remove the buffer function  */
        // Get output cache , otherwise imagepng Will output the picture to the browser 
        ob_start();
        imagepng($img);
        imagedestroy($img);
        $contents = ob_get_contents();
        ob_end_clean();
        return $contents;
    }

The method of mosaic picture in the middle area of QR code ：

  /** *  Mosaic the picture in the middle of the QR code  * @param $QR  QR code data stream . such as file_get_contents(imageurl) Return to the East , Or wechat to the returned Dongdong  * @param $logo  The data flow of the picture in the middle . such as file_get_contents(imageurl) Return to the East  * @return  Return picture data stream  */
    public function qrcodeWithLogo($QR, $logo,$shape) {
    
        $QR = imagecreatefromstring($QR);
        $logo = imagecreatefromstring($logo);
        $QR_width = imagesx($QR);// QR code image width 
        $QR_height = imagesy($QR);// QR code image height 
        $logo_width = imagesx($logo);//logo Image width 
        $logo_height = imagesy($logo);//logo Picture height 
        if ($shape == 1 ) {
    
            $logo_qr_width = $QR_width / 2.2;// After the combination logo Width ( Take up... Of QR code 1/2.2)
        } else {
    
            $logo_qr_width = $QR_width / 4;// After the combination logo Width ( Take up... Of QR code 1/4)
        }
        $scale = $logo_width / $logo_qr_width;//logo Width scaling ratio ( The width of itself / Combined width )
        $logo_qr_height = $logo_height / $scale;// After the combination logo Height 
        $from_width = ($QR_width - $logo_qr_width) / 2;// After the combination logo The coordinate point of the upper left corner 
        /** *  Recombine the picture and resize  * imagecopyresampled()  Put an image ( Source image ) Copy a square area in to another image  */
        imagecopyresampled($QR, $logo, $from_width, $from_width, 0, 0, $logo_qr_width, $logo_qr_height, $logo_width, $logo_height);
        /** *  If you want to output pictures directly , It should be set first header.header("Content-Type: image/png; charset=utf-8"); *  And remove the buffer function  */
        // Get output cache , otherwise imagepng Will output the picture to the browser 
        ob_start();
        imagepng($QR);
        imagedestroy($QR);
        imagedestroy($logo);
        $contents = ob_get_contents();
        ob_end_clean();
        return $contents;
    }