在javascript中打开带有来自url的欢迎消息的fb messenger

<script>
  window.fbAsyncInit = function() {
    FB.init({
      appId      : 'YOUR_APP_ID',
      xfbml      : true,
      version    : 'v13.0'
    });
  };

  (function(d, s, id){
     var js, fjs = d.getElementsByTagName(s)[0];
     if (d.getElementById(id)) {return;}
     js = d.createElement(s); js.id = id;
     js.src = "https://connect.facebook.net/en_US/sdk.js";
     fjs.parentNode.insertBefore(js, fjs);
   }(document, 'script', 'facebook-jssdk'));
</script>

<button onclick="openMessenger()">打开Messenger</button>

function openMessenger() {
  var welcomeMessageUrl = 'https://example.com/welcome-message'; // 替换为实际的欢迎消息URL

  FB.ui({
    method: 'send',
    link: welcomeMessageUrl
  });
}