我现在有这样的东西FuturecheckAvailability(Stringemail)async{varclient=newhttp.Client();varresponse=awaitclient.get(host);boolresult;if(response.statusCode==404){result=true;}elseif(response.statusCode==200){result=false;}client.close();returnresult;}我从一个普通的非aysnc函数调用上面的方法这样voidtest(){checkAvailability(em
