vb中的组合框中的两个值 [英] Two values inside a combobox in vb

问题描述

我想要创建一个包含两个字段的组合框。

i want to create a combobox with two fields inside.

到目前为止，这是我的代码。

它只能显示区域数字，但我想在一行显示区域名称。任何人都可以帮助我这个？任何帮助将非常感激。非常感谢你

so far, this is my code.
it can only display the area number but i want to display also the area name in a single line. can anyone help me with this? any help will be greatly appreciated. thank you so much

  Sub getarea()
    Try
        Call MyConnection()
        Sql = "select AREA_NO as 'Anum', AREA_NAME as 'Aname', AREA_LOCX as 'Alocx' from area"
        Dim cmd As New MySqlCommand(Sql, Con)
        Dim reader As MySqlDataReader
        reader = cmd.ExecuteReader
        Try
            Dim comboarea As New DataTable
            comboarea.Load(reader)
            cboareano2.DataSource = comboarea
            cboareano2.DisplayMember = "Anum"
            cboareano2.ValueMember = "Anum"
            cboareano2.SelectedIndex = -1

        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    Catch ex As Exception
        MsgBox(ex.Message)
        Con.Close()
    End Try
End Sub


Private Sub cboAreaNo_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboAreaNo.SelectedIndexChanged
    Try
        Call MyConnection()
        Sql = "select AREA_NAME, AREA_LOCX from area where AREA_NO=@Anum"
        Dim cmd As New MySqlCommand
        With cmd
            .CommandText = Sql
            .Connection = Con
            .Parameters.AddWithValue("@Anum", cboAreaNo.SelectedValue)
            .ExecuteNonQuery()
        End With
        Dim reader As MySqlDataReader
        reader = cmd.ExecuteReader
        Try
            If reader.Read Then
                txtlocx.Text = reader.GetString(1)
                reader.Close()
            End If
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    Catch ex As Exception
        Con.Close()
    End Try

推荐答案

您在绑定组合框时犯了一些错误，您是
分配<$ DisplayMember 字段以及
ValueMember 字段。因此 SelectedItem 和 SelectedValue都是
Area_Number。

You are makes some mistake in binding the combobox, you are assigning Anum to both DisplayMember field as well as to the ValueMember field. so the SelectedItem and SelectedValue both are the Area_Number`.

所以你必须做的是：
重新编码如下的绑定代码片段

So what you have to do is that: Recode the binding snippet as follows

    Dim comboarea As New DataTable
    comboarea.Load(reader)
    cboareano2.DataSource = comboarea
    cboareano2.DisplayMember = "Aname"
    cboareano2.ValueMember = "Anum"
    cboareano2.SelectedIndex = -1

您可以通过 cboareano2.Text 或
取得Area_Name cboareano2.SelectedItem.Text

• 您将通过 cboareano2.SelectedValue

获得Area_Code

• 如果要同时显示代码然后在查询中修改如下：

  • Now you can take the Area_Name through cboareano2.Text or cboareano2.SelectedItem.Text
  • You will get the Area_Code through cboareano2.SelectedValue

  • If you want to display both the code and name then make change in the query as follows:

     Sql = "select AREA_NO as 'Anum', CONCAT(AREA_NO,'-',AREA_NAME) as 'Aname', AREA_LOCX as 'Alocx' from area"
    

    
    
    <

    and bind the result as i mentioned above.

    这篇关于vb中的组合框中的两个值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！