mysql - 使用过滤器填充组合框

Question

我有一个包含以下列的数据库:

RegNumber | LastName | FirstName | OOPVB | DataComms | ModelsDB | MAB | OB | CF

我想用列 OOPVB,DataComms,ModelsDB,MAB,OB 和 CF 填充组合框。

我只能使用以下代码对单个列执行此操作:

Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
    mysqlConn = New MySqlConnection
    mysqlConn.ConnectionString =
    "server=127.0.0.1;userid=root;database=studentsresults1"
    Dim SDA As New MySqlDataAdapter
    Dim dbDataSet As New DataTable
    Dim bSource As New BindingSource

    Try
        mysqlConn.Open()
        Dim Query As String
        Query = "select * from studentsresults1.courses"
        SQLcmd = New MySqlCommand(Query, mysqlConn)
        SDA.SelectCommand = SQLcmd
        SDA.Fill(dbDataSet)
        bSource.DataSource = dbDataSet
        DataGridView1.DataSource = bSource
        SDA.Update(dbDataSet)


        mysqlConn.Close()

    Catch ex As MySqlException
        MessageBox.Show(ex.Message)

    Finally
        mysqlConn.Dispose()

    End Try


End Sub

如何对多列执行此操作？请帮忙

Answer 1

如果我理解正确的话，您想用您所说的“标记”表中的列中的所有数据填充组合，对吗？

一种方法(确实丑陋但实用)是对其余列重复此操作，对另一列执行另一个 SQL 并以这种方式添加结果。

更简洁的方法是循环所有单元格:

Private Sub GetCourses()
    SQL.ExecQuery("SELECT OOPVB,DataComms,ModelsDB,MAB,OB, CF FROM marks")
    If SQL.RecordCount > 0 Then
        For Each r As DataRow In SQL.SQLDS.Tables(0).Rows
            For Each c in r.ItemArray
                ComboBox1.Items.Add(c.Value)
            Next
        Next
        ComboBox1.SelectedIndex = 0
    ElseIf SQL.Exception <> "" Then
        MsgBox(SQL.Exception)
    End If
End Sub