编写vb.net代码来检查餐馆包间是否可用，并将顾客预订信息插入到预订表格中。如果包间不可用，则提示用户选择其他时间或包间。

以下是一个简单的 VB.NET 代码示例，用于检查餐馆包间是否可用并将顾客预订信息插入预订表格。

' 数据库连接字符串
Dim connString As String = "Data Source=myServerAddress;Initial Catalog=myDataBase;User Id=myUsername;Password=myPassword;"
' 预订表格名称
Dim tableName As String = "Reservations"

' 输入参数 - 包间号和预订时间
Dim roomNumber As Integer = 1
Dim reservationTime As DateTime = DateTime.Parse("2021-08-01 18:00:00")

' 检查包间是否可用
Dim isAvailable As Boolean = CheckRoomAvailability(roomNumber, reservationTime, connString, tableName)

If isAvailable Then
    ' 包间可用，插入预订信息到表格
    Dim customerName As String = "John Doe"
    Dim numberOfGuests As Integer = 4
    InsertReservation(roomNumber, reservationTime, customerName, numberOfGuests, connString, tableName)

    ' 提示用户预订成功
    MessageBox.Show("您已成功预订包间 #" & roomNumber & " 在 " & reservationTime.ToString("yyyy-MM-dd HH:mm:ss") & " 的用餐。")
Else
    ' 包间不可用，提示用户选择其他时间或包间
    MessageBox.Show("包间 #" & roomNumber & " 在 " & reservationTime.ToString("yyyy-MM-dd HH:mm:ss") & " 不可用，请选择其他时间或包间。")
End If


' 检查包间是否可用的函数
Private Function CheckRoomAvailability(ByVal roomNumber As Integer, ByVal reservationTime As DateTime, ByVal connString As String, ByVal tableName As String) As Boolean
    Dim isAvailable As Boolean = True

    ' 创建数据库连接
    Using conn As New SqlConnection(connString)
        ' 创建 SQL 查询语句
        Dim sql As String = "SELECT COUNT(*) FROM " & tableName & " WHERE RoomNumber = @RoomNumber AND ReservationTime = @ReservationTime"

        ' 创建命令对象
        Using cmd As New SqlCommand(sql, conn)
            ' 添加参数
            cmd.Parameters.AddWithValue("@RoomNumber", roomNumber)
            cmd.Parameters.AddWithValue("@ReservationTime", reservationTime)

            ' 打开连接并执行查询
            conn.Open()
            Dim count As Integer = CInt(cmd.ExecuteScalar())

            ' 如果有预订，则包间不可用
            If count > 0 Then
                isAvailable = False
            End If
        End Using
    End Using

    Return isAvailable
End Function


' 插入预订信息到表格的函数
Private Sub InsertReservation(ByVal roomNumber As Integer, ByVal reservationTime As DateTime, ByVal customerName As String, ByVal numberOfGuests As Integer, ByVal connString As String, ByVal tableName As String)
    ' 创建数据库连接
    Using conn As New SqlConnection(connString)
        ' 创建 SQL 插入语句
        Dim sql As String = "INSERT INTO " & tableName & " (RoomNumber, ReservationTime, CustomerName, NumberOfGuests) VALUES (@RoomNumber, @ReservationTime, @CustomerName, @NumberOfGuests)"

        ' 创建命令对象
        Using cmd As New SqlCommand(sql, conn)
            ' 添加参数
            cmd.Parameters.AddWithValue("@RoomNumber", roomNumber)
            cmd.Parameters.AddWithValue("@ReservationTime", reservationTime)
            cmd.Parameters.AddWithValue("@CustomerName", customerName)
            cmd.Parameters.AddWithValue("@NumberOfGuests", numberOfGuests)

            ' 打开连接并执行插入
            conn.Open()
            cmd.ExecuteNonQuery()
        End Using
    End Using
End Sub

请注意，该示例仅提供了一个简单的框架，您需要根据您的具体情况进行修改和扩展。另外，您需要将数据库连接字符串和表格名称替换为您自己的值。