javascript - 从 Cloud Firestore 中提取时，时间戳以字符串形式出现

Question

我已将时间戳数据提取到 html 数据属性中。

然后我想用它来填充将在模式弹出窗口上的日期表单字段。

但是，当尝试使用时，toDate()我收到了错误

Uncaught TypeError: moderationDate.toDate is not a function

为了测试，我使用警报来检查变量的值和数据类型moderationDate。我可以看到数据作为字符串存储在 html 数据属性中

<td data-moderateModerationDate="'+student.UnitGrades.IT6.Moderate.ModerationDate+'" >table data item</td> \

let moderationDate = $(this).attr("data-moderateModerationDate");

alert(moderationDate);
alert(typeof moderationDate);

• 警报 1 输出 -Timestamp(seconds=0, nanoseconds=0)
• 警报 2 输出 -string

谁能告诉我为什么这是一个字符串数据类型而不是原始时间戳？

标签： javascriptgoogle-cloud-firestore

Answer 1

HTML data attributes can only store strings, so you can't expect to put anything into it and expect to get exactly that thing back. The browser is converting it to a string when you store it, as you are adding it using string concatenation. I'd suggest trying to find another way to store this value.