【GAS】메일 취득

function GetMail(){
 var year = 2018;
 var month = 11;
 var startPeriod = "after:" + year + "/" + month + "/01";//取得開始月
 var lastDay = new Date(year, month, 0).getDate();//月末日
 var endPeriod = "before:" + year + "/" + month "/" + lastDay;//取得終了月
 var to = "to:指定メールアドレス";
 var searchThread = to + "," + startPeriod + "," + endPeriod;//検索条件
 var threads = GmailApp.search(searchThread);

 //検索条件「toが指定メールアドレスかつ2018/11/01〜2018/11/30」のメールをログ出力
 threads.forEach(function(thread,i,array){
 Logger.log(thread.getFirstMessageSubject()); 
 });
}