0

我想将对 DataGridView 所做的更改保存到数据库 MS SQL CE 中，但我不能，更改没有保存到数据库中......

这是代码（VB.net）：

    Private Sub Form1_Load(ByVal sender As System.Object, 
        ByVal e As System.EventArgs) handles MyBase.Load

        Dim con As SqlCeConnection = New SqlCeConnection(@"Data  Source=C:\Users\utente\Documents\test.sdf")

        Dim cmd As SqlCeCommand = New SqlCeCommand("SELECT * FROM mytable", con)

        con.Open()
        myDA = New SqlCeDataAdapter(cmd)
        Dim builder As SqlCeCommandBuilder = New SqlCeCommandBuilder(myDA)
        myDataSet = New DataSet()
        myDA.Fill(myDataSet, "MyTable")
        DataGridView1.DataSource = myDataSet.Tables("MyTable").DefaultView
        con.Close()
        con = Nothing

    End Sub



    Private Sub edit_rec()

        Dim txt1, txt2 As String
        Dim indice As Integer = DataGridView1.CurrentRow.Index

        txt1 = DataGridView1(0, indice).Value.ToString '(0 is the first column of datagridview)
        txt2 = DataGridView1(1, indice).Value.ToString '(1 is the second)        MsgBox(txt1 + "  " + txt2)
        '
        DataGridView1(0, indice).Value = "Pippo"
        DataGridView1(1, indice).Value = "Pluto"
        '
        Me.Validate()
        Me.myDA.Update(Me.myDataSet.Tables("MyTable"))
        Me.myDataSet.AcceptChanges()
        '
    End Sub

谢谢你的任何建议。

4

3 回答 3

0

您需要使用 myDA.Update，它将提交更改。这是因为您所做的任何更改都是在该数据集的本地实例中进行的。因此，就像任何其他变量一样被处理掉。

...我可以在您的 edit_rec 子中看到这一点，但是调用它的是什么 - 您发布的代码中没有任何内容。

于 2013-08-23T14:17:37.603 回答
0

我想你想用你的连接字符串添加@

SqlConnection con;

      con = New SqlConnection(@"Data  Source=C:\Users\utente\Documents\test.sdf");
于 2014-09-11T08:56:45.927 回答
0

可能有点晚了。

在表单加载事件中，您打开和关闭连接。此外，所有都是局部变量，在离开子时会丢失任何值或数据

Public Class Form1



        Dim con As SqlCeConnection

        Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load

            con = New SqlCeConnection(@"Data  Source=C:\Users\utente\Documents\test.sdf")

            Dim cmd As SqlCeCommand = New SqlCeCommand("SELECT * FROM mytable", con)

            con.Open()
            myDA = New SqlCeDataAdapter(cmd)
            Dim builder As SqlCeCommandBuilder = New SqlCeCommandBuilder(myDA)
            myDataSet = New DataSet()
            myDA.Fill(myDataSet, "MyTable")
            DataGridView1.DataSource = myDataSet.Tables("MyTable").DefaultView
            cmd.Dispose()

        End Sub

***Put the closing of connection here instead or somewhere else suitable when you don't use it anymore***

        Private Sub Form1_FormClosed(sender As Object, e As System.Windows.Forms.FormClosedEventArgs) Handles Me.FormClosed

            con.Close()
            con = Nothing

        End Sub

        Private Sub edit_rec()

            Dim txt1, txt2 As String
            Dim indice As Integer = DataGridView1.CurrentRow.Index

            txt1 = DataGridView1(0, indice).Value.ToString '(0 is the first column of datagridview)
            txt2 = DataGridView1(1, indice).Value.ToString '(1 is the second)        MsgBox(txt1 + "  " + txt2)
            '
            DataGridView1(0, indice).Value = "Pippo"
            DataGridView1(1, indice).Value = "Pluto"
            'You code to update goes here and not in my scope of answer

       End Sub

    End Class
于 2014-04-25T02:41:32.197 回答