VBNET数据库编程基础教程(17)

Private Sub btnEnd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnEnd.Click

Me.BindingContext(myDataSet, ″student″).Position = Me.BindingContext(myDataSet, ″student″).Count - 1

End Sub

(4)翻阅到第一条记录：

双击“第一条记录”按钮，在代码窗中输入以下代码：

Private Sub btnFirst_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnFirst.Click

Me.BindingContext(myDataSet, ″student″).Position = 0

End Sub

说明：为了代码书写方便，我们可以先定义一个BindingManagerBase对象myBind，如myBind = Me.BindingContext (myDataSet, ″student″ )，于是以上各句代码均可以简写成：

向上翻阅一条记录：myBind.Position = myBind.Position - 1

向下翻阅一条记录：myBind.Position = myBind.Position + 1

翻阅到最后一条记录：myBind.Position=myBind.count - 1

翻阅到第一条记录：myBind.Position = 0

2.删除数据记录

双击“删除记录”按钮，在代码窗中输入以下代码：

Private Sub btnDel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDel.Click

Dim ConnectionString As String = ″ Provider = Microsoft.Jet.OLEDB.4.0; Data Source = e:\My Documents\db1.mdb″

Dim myConn As OleDbConnection = New OleDbConnection()

myConn.ConnectionString = ConnectionString

myConn.Open()