VB.NET數據集更新

Question

爲什麼我的代碼集在DataSet中沒有更新？然後它轉到錯誤。請任何人檢查這個代碼，並指出我失蹤的地方。提前致謝！

Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click 

    Dim conxMain As New SqlConnection("Data Source=SERVER;Initial Catalog=DBTest;Persist Security Info=True;User ID=username;Password=pwds") 

    Dim dadPurchaseInfo As New SqlDataAdapter 
    Dim dsPurchaseInfo As New DataSet1 
    Try 
     Dim dRow As DataRow 

     conxMain.Open() 

     Dim cmdSelectCommand As SqlCommand = New SqlCommand("SELECT * FROM Stock", conxMain) 
     cmdSelectCommand.CommandTimeout = 30 

     dadPurchaseInfo.SelectCommand = cmdSelectCommand 
     Dim builder As SqlCommandBuilder = New SqlCommandBuilder(dadPurchaseInfo) 

     dadPurchaseInfo.Fill(dsPurchaseInfo, "Stock") 


     For Each dRow In dsPurchaseInfo.Tables("Stock").Rows 
      If CInt(dRow.Item("StockID").ToString()) = 2 Then 
       dRow.Item("StockCode") = "Re-Fashion[G]" 
      End If 

     Next 
     dadPurchaseInfo.Update(dsPurchaseInfo, "Stock") 

    Catch ex As Exception 
     MsgBox("Error : ") 
    Finally 
     If dadPurchaseInfo IsNot Nothing Then 
      dadPurchaseInfo.Dispose() 
     End If 

     If dsPurchaseInfo IsNot Nothing Then 
      dsPurchaseInfo.Dispose() 
     End If 

     If conxMain IsNot Nothing Then 
      conxMain.Close() 
      conxMain.Dispose() 
     End If 
    End Try 
End Sub 

Answer 1

請問您在循環條件得到執行（！設置一個斷點）在哪裏錯誤拋出？什麼錯誤？

另外，它爲什麼使用ToString呢？這似乎是多餘的。

If CInt(dRow.Item("StockID")) = 2 Then 

應該足夠了。

最後，您要執行冗餘清理：

If conxMain IsNot Nothing Then 
    conxMain.Close() 
    conxMain.Dispose() 
End If 

Dispose意味着Close - 沒有必要進行這兩種操作：

Close和Dispose在功能上等同。

[Source: MSDN]

Answer 2

您的dataAdapter是否有更新命令？

（它看起來像它不會 - 所以它不知道做什麼用更新....）

下面是一個更新命令例如：（與3列的僱員表 - 爲列舉如下：？

UPDATE [Employee] 
SET [name] = @name 
    , [manager] = @manager 
WHERE (([id] = @Original_id) AND 
     ((@IsNull_name = 1 AND [name] IS NULL) OR 
          ([name] = @Original_name)) AND 
     ((@IsNull_manager = 1 AND [manager] IS NULL) OR 
           ([manager] = @Original_manager))); 


SELECT id 
    , name 
    , manager 
FROM Employee 
WHERE (id = @id) 

你可以看到它是一個可以處理任何領域變化的一般更新

Answer 3

我是從由Konard魯道夫我的程序的糾錯！

Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click 

    Dim conxMain As New SqlConnection("Data Source=SERVER;Initial Catalog=DBTest;Persist Security Info=True;User ID=username;Password=pwds") 

    Dim dadPurchaseInfo As New SqlDataAdapter 
    Dim dsPurchaseInfo As New DataSet1 
     Try 
      Dim dRow As DataRow 

      conxMain.Open() 

      dadPurchaseInfo.SelectCommand = New SqlCommand("SELECT * FROM Stock", conxMain) 
      Dim builder As SqlCommandBuilder = New SqlCommandBuilder(dadPurchaseInfo) 


      dadPurchaseInfo.Fill(dsPurchaseInfo, "Stock") 

      For Each dRow In dsPurchaseInfo.Tables("Stock").Rows 
       If CInt(dRow.Item("StockID")) = 2 Then 
        dRow.Item("StockCode") = "Re-Fashion(H)" 
       End If 

      Next 
      dadPurchaseInfo.Update(dsPurchaseInfo, "Stock") 
     Catch ex As Exception 
      MsgBox("Error : " & vbCrLf & ex.Message) 
     Finally 
      If dadPurchaseInfo IsNot Nothing Then 
       dadPurchaseInfo.Dispose() 
      End If 

      If dsPurchaseInfo IsNot Nothing Then 
       dsPurchaseInfo.Dispose() 
      End If 

      If conxMain IsNot Nothing Then 
       conxMain.Dispose() 
      End If 
     End Try 
    End Sub 

上述一組代碼可以使用DataSet進行更新！感謝stackoverflow社區和誰回答我的問題。

這裏是參照：

• How To Update a SQL Server Database by Using the SqlDataAdapter Object in Visual Basic .NET
• How to update a database from a DataSet object by using Visual Basic .NET

P.S：像o.k.w表示：表必須具有主鍵。感謝o.k.w！

Answer 4

--MENU-- 
Dim login As New LoginClass 
login.ShowDialog() 

--CONEXION-- 
Private conec As SqlConnection 
Dim stringCon As String = "Data Source= ;Initial Catalog=;Persist Security Info=True;User ID=;Password=" 
Public ReadOnly Property prConec() As Object 
    Get 
     Return conec 
    End Get 
End Property 
Public Sub Conectar() 
    Try 
     conec = New SqlConnection(stringCon) 
     If conec.State <> ConnectionState.Open Then 
      conec.Open() 
     End If 
    Catch ex As Exception 
     MessageBox.Show(ex.Message) 
    End Try 
End Sub 

--BUSCAR-- 
funciones.Conectar() 
Dim coman As New SqlCommand("sp_cliente", funciones.prConec) 
Dim dt As New DataTable 
coman.CommandType = CommandType.StoredProcedure 
coman.Parameters.Add("@i_operacion", SqlDbType.Char, 1, ParameterDirection.Input).Value = "B" 
dt.Load(coman.ExecuteReader()) 
grdClientes.DataSource = dt 

--INSERTAR-- 
funciones.Conectar() 
Dim coman As New SqlCommand("sp_articulo", funciones.prConec) 
coman.CommandType = CommandType.StoredProcedure 
coman.Parameters.Add("@i_operacion", SqlDbType.Char, 1, ParameterDirection.Input).Value = "I" 
coman.ExecuteNonQuery() 
Buscar() 
Limpiar() 

--COMBO-- 
Dim dt As New DataTable 
dt.Columns.Add("Codigo") 
dt.Columns.Add("Descripcion") 
Dim dr1 As DataRow = dt.NewRow 
dr1.Item("Codigo") = "A" 
dr1.Item("Descripcion") = "Activo" 
dt.Rows.Add(dr1) 
Dim dr2 As DataRow = dt.NewRow 
dr2.Item("Codigo") = "I" 
dr2.Item("Descripcion") = "Inactivo" 
dt.Rows.Add(dr2) 
cmbEstado.DataSource = dt 
cmbEstado.ValueMember = "Codigo" 
cmbEstado.DisplayMember = "Descripcion" 

--GRIDVIEW-- 
--1-- 
Dim grdFila As DataGridViewRow = grdClientes.CurrentRow 
txtCedula.Text = grdFila.Cells(0).Value 
--2-- 
If DataGridProductos.CurrentCell.ColumnIndex = 0 Then 
    Dim FLstArticulos As New FLstArticulos 
    FLstArticulos.ShowDialog() 
    DataGridProductos.CurrentRow.Cells(0).Value = FLstArticulos.PrIdArticulo 
End If 

--GRIDVIEW.CELLENDEDIT-- 
If DataGridProductos.CurrentCell.ColumnIndex = 3 Then 
    Dim precio As New Double 
    Dim cantidad As New Double 
    precio = CDbl(grdRow.Cells(2).Value) 
    cantidad = CDbl(grdRow.Cells(3).Value) 
    DataGridProductos.CurrentRow.Cells(4).Value = PLTotalFilaItem(cantidad, precio) 
    PLCargaTotales() 
End If 

Sub PLCargaTotales() 
    Dim subTotal As Double 
    Dim iva As Double 
    For Each grd As DataGridViewRow In DataGridProductos.Rows 
     If Not String.IsNullOrEmpty(grd.Cells(4).Value) Then 
      subTotal = subTotal + CDbl(grd.Cells(4).Value) 
     End If 
    Next grd 
    txtSubtotal.Text = subTotal.ToString 
    iva = Decimal.Round(subTotal`enter code here` * 0.12) 
    txtIva.Text = iva.ToString 
    txtTotalPagar.Text = (subTotal + iva).ToString 
End Sub