ionic2在forEach循环中等待Promise

Question

  var listOfItems = [1, 2, 3, 4, 5];

  listOfItems.forEach(
    item => {
      this.createTimeout(3000)
      .then(
        () => {
          console.log(item);
        })   
  });

  createTimeout(timeout) {
      return new Promise((resolve, reject) => {
          setTimeout(() => resolve(null),timeout)
      })   }

我想等待Promise回复＆＃39; createTimeout＆＃39;然后转到下一个元素。有什么想法吗？