Firebase数据检索返回复杂对象

Question

我想从firebase检索数据并显示在我尝试了大多数方法的网站上，但不适用于我。

这是我的火力发源地

 "transactions" : {
    "8527z732x5e5RZnaWlYnvXLQv1Z2" : {
      "102" : {
        "trans_amount" : "20",
        "trans_date" : "23/11/2018"
      },
      "103" : {
        "trans_amount" : 240,
        "trans_date" : "23/12/2018"
      }
    },
    "WfEQmVDBXeXFqrmzNslIPhD0UqQ2" : {
      "102" : {
        "trans_amount" : "20",
        "trans_date" : "23/11/2018"
      }
    }
  }

这是我的检索代码

ref.on("child_added", function (snapshot) {
    PrintData.innerText = ""; // We got a new value, so clear the existing 
    HTML
    snapshot.forEach(function (childSnapshot) {
        var childData = childSnapshot.val();
        //showing single object value
        console.log(childData);
        PrintData.innerText += "trans_amount: " + childData.trans_amount + " 
        trans_date: " + childData.trans_date + "
        ";
    });
});

这是我的输出

output