Question

我正在尝试获取表单加载的一些值，这将是自动的，因为用户不应该输入这些值。我正在以子例程的形式进行这些操作，因此它看起来更整洁，并且我更容易重用。贝娄，你可以看看我有的5个子，第一个完美的工作，其余的不！我不明白，因为它们基于同样的原则！

Sub CustomerNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    conn.Open()

    Dim Rows As Integer 'Used For Customer
    Dim sql As String = "SELECT * FROM Customer"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Customer")
    Rows = ds.Tables("Customer").Rows.Count
    Customer_IDTextBox.Text = Rows
End Sub
Sub OrderNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    conn.Open()

    Dim ds As New DataSet
    Dim sql As String = "SELECT * FROM Order"
    Dim Rows As Integer 'Used for Order Table
    Dim da As OleDb.OleDbDataAdapter
    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds.Tables(0))
    Rows = ds.Tables(0).Rows.Count
    NewOrderID.Text = Rows + 1
    Order_IDTextBox.Text = NewOrderID.Text

End Sub
Sub PizzaNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    conn.Open()

    Dim Rows As Integer 'Used for Pizza Table
    Dim sql As String = "SELECT * FROM Pizza"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Pizza")
    Rows = ds.Tables("Pizza").Rows.Count
    NewPizzaID.Text = Rows + 1
    Pizza_IDTextBox.Text = NewPizzaID.Text

End Sub
Sub DrinksNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    conn.Open()

    Dim Rows As Integer 'Used for Drinks Table
    Dim sql As String = "SELECT * FROM Drinks"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Drinks")
    Rows = ds.Tables("Drinks").Rows.Count
    NewDrinksID.Text = Rows + 1
    Drinks_IDTextBox.Text = NewDrinksID.Text

End Sub
Sub SidesNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    conn.Open()

    Dim Rows As Integer 'Used for Sides Table
    Dim sql As String = "SELECT * FROM Sides"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Sides")
    Rows = ds.Tables("Sides").Rows.Count
    NewSidesID.Text = Rows + 1
    Sides_IDTextBox.Text = NewSidesID.Text

End Sub

以下是我在表单加载时调用的位：

Private Sub frmProducts_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    SetValues()

    CustomerNo()
    OrderNo()
    PizzaNo()
    DrinksNo()
    SidesNo()

End Sub

set values sub工作正常，这不是问题，只是在beggining设置值。它没有显示错误或什么都没有，只是代码似乎没有工作，它除了第一个CustomerNo（）位之外什么都不做。

提前再次感谢。

此致

何

Answer 1

这里有几个错误：1）“订单”一词几乎是任何数据库中的保留字。所以你必须分隔它，否则DB会抛出错误。 2）在数据集中，您正在尝试填充未创建的表（0）（因此不存在）。试试这段代码：

'It is always best to put settings like this in a private property.'  
'Better still, learn how to look it up from your project settings (file)'
Private ReadOnly Property ConnString As String
    Get
        return "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=H:\Year 2\Unit 17 Project Planning\Workto do\PizzaPalce\Program\DatabasePizzaPalace.accdb"
    End Get
End Property

Sub OrderNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = ConnString
    conn.Open()

    Dim ds As New DataSet
    Dim sql As String = "SELECT * FROM [Order]"
    Dim Rows As Integer 'Used for Order Table'
    Dim da As OleDb.OleDbDataAdapter
    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds)
    Rows = ds.Tables(0).Rows.Count
    NewOrderID.Text = Rows + 1
    Order_IDTextBox.Text = NewOrderID.Text
End Sub

Sub PizzaNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = ConnString
    conn.Open()

    Dim Rows As Integer 'Used for Pizza Table'
    Dim sql As String = "SELECT * FROM Pizza"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Pizza")
    Rows = ds.Tables("Pizza").Rows.Count
    NewPizzaID.Text = Rows + 1
    Pizza_IDTextBox.Text = NewPizzaID.Text
End Sub

Sub DrinksNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = ConnString
    conn.Open()

    Dim Rows As Integer 'Used for Drinks Table'
    Dim sql As String = "SELECT * FROM Drinks"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Drinks")
    Rows = ds.Tables("Drinks").Rows.Count
    NewDrinksID.Text = Rows + 1
    Drinks_IDTextBox.Text = NewDrinksID.Text
End Sub

Sub SidesNo()
    Dim conn As New System.Data.OleDb.OleDbConnection()
    conn.ConnectionString = ConnString
    conn.Open()

    Dim Rows As Integer 'Used for Sides Table'
    Dim sql As String = "SELECT * FROM Sides"
    Dim da As OleDb.OleDbDataAdapter
    Dim ds As New DataSet

    da = New OleDb.OleDbDataAdapter(sql, conn)
    da.Fill(ds, "Sides")
    Rows = ds.Tables("Sides").Rows.Count
    NewSidesID.Text = Rows + 1
    Sides_IDTextBox.Text = NewSidesID.Text

End Sub

无法在表单加载上加载值！ VB SQL Access

1 个答案: