ComboBox值发生了变化 [英] ComboBox values getting changed

问题描述

关于我昨天的问题（如何从SQL数据表中填充组合框 [ ^ ]）我有一个新问题。



我的ComboBox填充了我的测试数据库中的3个条目。如果我点击ComboBox，我会得到3个条目，如果我没有选择一个，我只是再次点击ComboBox，它关闭，我可以无限重复这个广告...这就像我期望的那样。



如果我然后点击ComboBox并选择其中一个，让我们说中间的一个，DropDown关闭，选择在ComboBox中，再次，如我希望。



然而，如果我再次单击ComboBox（让我们假设我的用户选择了错误的选项），我做的选择现在是第一个条目，原始的第一个条目已经消失，第二个条目，我选择的条目，已被替换为文本System.Data.DataRowView（如果我将ValueMember设置为数据集中的名称）或者如果我将ValueMember设置为数据集中的ID，我的选择，当我重新打开ComboBox时，突出显示，仍然在第二位，但第一个条目已经消失，已被数字2替换...我想一想sitioning可能取决于DatsTable的排序。



如果我取消并重新运行，一切都恢复正常，所以没有任何东西真正被更新。

解决方案

这是我的代码，Tejas，例如......

 < span class =code-keyword>公开 类 KAmail_Form1 
 
 私有  Sub  KAmail_Form1_Load（sender  As  System。 Object ，e  As  System.EventArgs）句柄  MyBase  .Load 
 
  Me  .LeaguesTableAdapter.Fill（ Me 。 DB_KAmailDataSet.Leagues）
 
 KAmail_ComboBox1.SelectedIndex = -1 
 KAmail_ComboBox2.SelectedIndex =  0  
 
 结束  Sub  
 
 私有  Sub  KAmail_Button1_Click（发件人作为系统。对象，e  As  System.EventArgs）句柄 KAmail_Button1.Click 
 
 结束  Sub  
 
 私有  Sub  KAmail_Button2_Click（发件人作为系统。对象，e  As  System.EventArgs）句柄 KAmail_Button2.Click 
 我 .Close（）
 结束  Sub  
 
 结束 类 

我的方式不同，所以可以关闭/删除这个问题/主题。

As a follow on to my question of yesterday (How do I Populate a Combobox from a SQL Datatable[^]) I have a new question.

My ComboBox is populated with the 3 entries from my test Database. If I click on the ComboBox I get the 3 entries as I would expect, if I don't select one and I just click on the ComboBox again, it closes and I can repeat this ad infinitum ... this is as I would expect.

If I then click on the ComboBox and Select one of them, let's say the middle one, the DropDown closes and the Selection is in the ComboBox, again, as I would expect.

However, if I then click on the ComboBox again (let's assume my User has Selected the wrong option), the Selection I made is now the first entry, the original first entry has gone, and the second entry, the one I Selected, has been replaced with either the text "System.Data.DataRowView" (If I have the ValueMember set to the Name from the Dataset) or if I have the ValueMember set to the ID from the Dataset, my Selection, when I re-open the ComboBox, is highlighted, still in second place, but the first entry is gone and has been replaced by the Number "2" ... I think the positioning is probably down to Sorting of the DatsTable.

If I cancel and rerun, everything is back to normal so nothing is really being Updated.

解决方案

This is my code, Tejas, such as it is ...

Public Class KAmail_Form1

    Private Sub KAmail_Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

        Me.LeaguesTableAdapter.Fill(Me.DB_KAmailDataSet.Leagues)

        KAmail_ComboBox1.SelectedIndex = -1
        KAmail_ComboBox2.SelectedIndex = 0

    End Sub

    Private Sub KAmail_Button1_Click(sender As System.Object, e As System.EventArgs) Handles KAmail_Button1.Click

    End Sub

    Private Sub KAmail_Button2_Click(sender As System.Object, e As System.EventArgs) Handles KAmail_Button2.Click
        Me.Close()
    End Sub

End Class

I have done this differently, so this question / topic can be closed / deleted.

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