Question

我希望在插入直接进入Combobox的值后更新Combobox。可能我需要进行查询，我已经知道了。这是我目前获得的代码

    Private Sub UpdateComboBox()
    SQLCon = New SqlConnection
    SQLCon.ConnectionString = "...."
    Try
        SQLCon.Open()
        Dim Query As String
        Query = "SELECT Filetype FROM infofile GROUP BY Filetype"
        SqlCmd = New SqlCommand(Query, SQLCon)
        SQLDataReader = SqlCmd.ExecuteReader
        ComboBox1.DataSource = ComboBox1.Items.Add(Query)
        SQLCon.Close()
    Catch ex As SqlException
        MsgBox(ex.Message)
    Finally
        SQLCon.Dispose()
    End Try
End Sub

我想在插入内容后立即添加此方法。

此代码的格式为

SQLCon = New SqlConnection
        SQLCon.ConnectionString = "......"
        Try
            SQLCon.Open()
            Dim Query As String
            Query = "SELECT Filetype FROM infofile GROUP BY Filetype"
            SqlCmd = New SqlCommand(Query, SQLCon)
            SQLDataReader = SqlCmd.ExecuteReader
            While SQLDataReader.Read
                Dim fileType = SQLDataReader.GetString(0)
                DataGridView1.DataSource = ComboBox1.Items.Add(fileType)
            End While
            SQLCon.Close()
        Catch ex As SqlException
            MsgBox(ex.Message)
        Finally
            SQLCon.Dispose()
        End Try

Answer 1

试试这个：

Private Sub UpdateComboBox()
    SQLCon = New SqlConnection
    SQLCon.ConnectionString = "....."
    Try
        SQLCon.Open()
        Dim Query As String
        Query = "SELECT Filetype FROM infofile GROUP BY Filetype"
        SqlCmd = New SqlCommand(Query, SQLCon)
        Dim adapter As New SqlDataAdapter(SqlCmd)
        Dim table As New DataTable
        adapter.Fill(table)
        ComboBox1.DataSource = table
        ComboBox1.DisplayMember = "Filetype"
        SQLCon.Close()
        Return table
    Catch ex As SqlException
        MsgBox(ex.Message)
    Finally
        SQLCon.Dispose()
    End Try
End Sub

插入值后更新组合框

1 个答案: