Sql server 通过选择组合框中的项，将多个数据从sql绑定到标签

如何将sql中的多个数据绑定到标签如果我在组合框中选择了来自sql的项，这是我的代码：

    Private Sub cmboCourse_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmboCourse.SelectedIndexChanged

    If cmboCourse.Text = "ADVANCED COMPUTER TECHNICIAN" Then
        callMe()
    ElseIf cmboCourse.Text = "AUTOELECTRICITY" Then
        callMe()
    ElseIf cmboCourse.Text = "AUTOMOTIVE" Then
        callMe()
    End If

End Sub


Private Sub callMe()

Dim str As String = ("Data Source=PC1; User ID=sa; Password=pwd;Databasfriend")
Dim con As New SqlConnection(str)
Dim str1 As String = "SELECT * FROM tbl_course"
Dim da As New SqlDataAdapter(str1, con)
Dim dataset1 As New DataSet()
da.Fill(dataset1, "course")
lbl.DataBindings.Add("text", dataset1, "course.Course_Code")

end sub

这是我的桌子

 Course_Code      Course
 ACT              ADVANCED COMPUTER TECHNICIAN
 AE               AUTOELECTRICITY
 AM               AUTOMOTIVE

---

它只绑定一个数据，我想在一个特定的列中绑定多个数据示例我在组合框中选择一个课程AUTOMOTIVE如何绑定到标签，如果我选择AutoElectrical如何绑定到同一标签AutoElectrical如何绑定到同一标签这是未经测试的，如果它不起作用，请告诉我

Private Sub cmboCourse_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmboCourse.SelectedIndexChanged
    callMe(cmboCourse.Text)
End Sub


Private Sub callMe(ByVal course as String)

    Dim str As String = ("Data Source=PC1; User ID=sa; Password=pwd;Databasfriend")
    Dim con As New SqlConnection(str)
    Dim str1 As String = "SELECT * FROM tbl_course WHERE [Course]='" & course & "'"
    Dim da As New SqlDataAdapter(str1, con)
    Dim dataset1 As New DataSet()
    da.Fill(dataset1, "tbl_course")
    'lbl.DataBindings.Add("text", dataset1, "course.Course_Code")
    If dataset1.Tables("tbl_course").Rows.Count > 0 Then
        lbl.Text = dataset1.Tables("tbl_course").Rows(0)("Course_Code")
    Else
        MsgBox "Course [" & course & "] not found"
    End If

End Sub

请注意，在代码da.Filldataset1中，course指定表为“course”，而select语句从“tbl_course”表中进行选择。我假设后者是正确的名字

编辑1： 错误修复

编辑2： 调试

sc.Open Dim da作为新的SqlDataAdapter

    Dim dataset1 As New DataSet()
    Dim sql As New SqlCommand("Select * from book where Title='" + cmbtit.Text + "'", sc)

    da.SelectCommand = sql
    da.SelectCommand.ExecuteNonQuery()
    da.Fill(dataset1, "book")

    If dataset1.Tables("book").Rows.Count > 0 Then
        txtauthor.Text = dataset1.Tables("book").Rows(0)("Author")
    Else
        MsgBox("Author [" & cmbtit.Text & "] not found")
    End If
    sc.Close()

End Sub

---

使用lbl.Text=dataset1.Tablestbl\u course.Rows0Course\u codeCallmecmbourse.Text修复了此问题-在[course]之后对私有子调用和课程的讨论过多='&-未声明由于其保护级别，它可能无法访问。仅此而已。您没有更改callMe定义：Private Sub callMeByVal course as Stringsir我运行程序，然后在此lbl上出错。Text=dataset1.tabletBl_course.rows0 course_代码-对象引用未设置为对象的实例它指向的是什么？你真的有一个叫lbl的标签吗？或者你没有任何记录返回。如果dataset1.tablestbl_course.Rows.Count>0，则将语句放入其中