根据预加载的下拉列表项验证文本框输入 [英] Validating textbox input against pre-loaded dropdownlist items

问题描述

如何检查文本框中输入的日期是否在预先加载（从数据库）到下拉列表的日期范围内，而不必查询数据库？ 

How do I check if the date entered in a text box is in the range of dates that have been pre-loaded (from a database) into the drop down list without having to query the DB? 

每个客户ID都有一些加载到下拉列表中的日期集合。 我必须添加一个文本框，让用户输入日期以显示其帐户信息。 现在我必须确保客户在文本框中输入的日期
位于下拉列表中的集合中。 如果它不在列表中，如何将其默认为列表中的第一个上一个日期？ 

Each individual client ID has a certain collection of dates that are loaded into a dropdownlist.  I had to add a textbox to let the user enter a date to show their account info.  Now I have to make sure the date the client enters in the textbox is in the collection in the dropdownlist.  If it's not in the list, how do I make it default to the first previous date on the list? 

感谢任何人的帮助！

推荐答案

如果日期已经在（我假设组合框？），那么迭代组合框项目。

If the dates are already in the (I assume combobox?), then iterate through the combobox items.

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