VB.NET数据集更新

Question

为什么我的代码集在DataSet中没有更新？然后它转到错误。请任何人检查这个代码，并指出我失踪的地方。提前致谢！

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

请问您在循环条件得到执行（！设置一个断点）在哪里错误抛出？什么错误？

另外，它为什么使用ToString呢？这似乎是多余的。

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

应该足够了。

最后，您要执行冗余清理：

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

Dispose意味着Close - 没有必要进行这两种操作：

Close和Dispose在功能上等同。

[Source: MSDN]

Answer 2

您的dataAdapter是否有更新命令？

（它看起来像它不会 - 所以它不知道做什么用更新....）

下面是一个更新命令例如：（与3列的雇员表 - 为列举如下：？

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) 

你可以看到它是一个可以处理任何领域变化的一般更新

Answer 3

我是从由Konard鲁道夫我的程序的纠错！

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 

上述一组代码可以使用DataSet进行更新！感谢stackoverflow社区和谁回答我的问题。

这里是参照：

• 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：表必须具有主键。感谢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