1、先获取ACCESS_TOKEN：
代码如下

$tokenUrl="https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".$this->appid."&secret=".$this->secret;
    $getArr=array();
    $tokenArr=json_decode($this->send_post($tokenUrl,$getArr,"GET"));
    $access_token=$tokenArr->access_token;

send_post函数:
代码如下

function send_post($url, $post_data,$method='POST') {
    $postdata = http_build_query($post_data);
    $options = array(
      'http' => array(
        'method' => $method, //or GET
        'header' => 'Content-type:application/x-www-form-urlencoded',
        'content' => $postdata,
        'timeout' => 15 * 60 // 超时时间（单位:s）
      )
    );
    $context = stream_context_create($options);
    $result = file_get_contents($url, false, $context);
    return $result;
  }

2、生成二维码：
代码如下

$path="pages/index?query=1";
    $width=430;
    $post_data='{"path":"'.$path.'","width":'.$width.'}';
    $url="https://api.weixin.qq.com/cgi-bin/wxaapp/createwxaqrcode?access_token=".$access_token;
    $result=$this->api_notice_increment($url,$post_data);

api_notice_increment函数:
代码如下

function api_notice_increment($url, $data){
    $ch = curl_init();
    $header = "Accept-Charset: utf-8";
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
    curl_setopt($curl, CURLOPT_HTTPHEADER, $header);
    curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (compatible; MSIE 5.01; Windows NT 5.0)');
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
    curl_setopt($ch, CURLOPT_AUTOREFERER, 1);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $tmpInfo = curl_exec($ch);
    //     var_dump($tmpInfo);
    //    exit;
    if (curl_errno($ch)) {
      return false;
    }else{
      // var_dump($tmpInfo);
      return $tmpInfo;
    }
  }

3、根据返回的二进制数据生成图片并上传到自己的服务器
代码如下

file_put_contents($filepath, $result)

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