Question

所以我有一个访问数据库，其中包含三列：制造，夹具和模式

我正在使用以下代码在表单中创建级联组合框。

Imports System.Data.OleDb


Public Class Add_Fixtures
   Dim con As New OleDbConnection
   Dim constring As String
   Dim cmd As New OleDbCommand
   Dim dr As OleDbDataReader
   Dim cmd1 As New OleDbCommand
   Dim dr1 As OleDbDataReader
   Dim cmd2 As New OleDbCommand
   Dim dr2 As OleDbDataReader

Private Sub Add_Fixtures_Load(sender As Object, e As EventArgs) Handles Me.Load
    constring = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|/FixtureLibrary.accdb"
    With con
        .ConnectionString = constring
        .Open()
    End With

    With cmd
        .Connection = con
        .CommandType = CommandType.Text
        .CommandText = "SELECT DISTINCT Fixtures.Manufacture from Fixtures;"
    End With

    dr = cmd.ExecuteReader()

    While dr.Read
        cbManufacture.Items.Add(dr("Manufacture"))
    End While

    With cmd1
        .Connection = con
        .CommandType = CommandType.Text
        .CommandText = "SELECT  from Fixtures where [Manufacture]='" & Me.cbManufacture.Text & "';"
    End With

    dr1 = cmd1.ExecuteReader()

    While dr1.Read
        cbFixture.Items.Add(dr1("Fixture"))
    End While

    With cmd2
        .Connection = con
        .CommandType = CommandType.Text
        .CommandText = "SELECT DISTINCT Fixtures.Mode from Fixtures where [Fixture] ='" & Me.cbFixture.Text & "';"
    End With

    dr2 = cmd2.ExecuteReader()

    While dr2.Read
        cbMode.Items.Add(dr2("Mode"))
    End While
End Sub
End Class

但是在这一行：dr1 = cmd1.ExecuteReader（）

我收到此错误

System.Data.OleDb.OleDbException：“ SELECT语句包含一个保留字或一个拼写错误或丢失的参数名称，或者标点符号不正确。”

任何人都知道是什么原因或原因吗？

欢呼

Answer 1

您不选择任何字段，并且属性 Text 仅对具有焦点的控件有效，因此：

   .CommandText = "SELECT * from Fixtures where [Manufacture]='" & Me.cbManufacture.Value & "';"

级联组合框的Visual Basic ACCDB文件读取

1 个答案: