您当前的位置: 我写了一个Windows小程序，使其可以对Access数据库作写入操作，并且Access数据库用DataGridView控件实时显示，以期望实现数据一经插入，DataGridView即可立即更新变化！
可是我发现当我在Access数据库中成功插入一行记录后，DataGridView并没有更新，但关闭了程序，再重新进入程序后，刚才插入的记录才可以显示出来。
如果不退出重新启动程序，而是连续插入多个记录的话，那么第一次插入操作是看不到DataGridView有任何更新的，只有插入第二行记录的时候，上一次插入的记录才可以显示出来。
以此类推，最后一次插入的记录始终都不会显示，还是需要重新启动应用程序才可正确显示，具体如下，请问为什么会这样的？
我应该怎样修改才可以让DataGridView实时显示数据库的更改？谢谢！
这是类库 dbFunction 的全部代码，我在UserPermission中设置了两个可读写的属性，分别为：Name和Password，用以暂存Form1传过来的用户名和密码，以供类库内部的Sub Add()使用。
- VB.NET code
'''此类库名称为 dbFunction
'''需要在程序中使用 Imports dbFunction 语句引用
Imports System.Data.OleDb
Public Class UserPermission
Dim _name As String
Dim _password As String
Public Property Name() As String
Get
Return _name
End Get
Set(ByVal value As String)
_name = value
End Set
End Property
Public Property Password() As String
Get
Return _password
End Get
Set(ByVal value As String)
_password = value
End Set
End Property
Private Function GetConnection() As OleDbConnection
Dim dbName As String
Dim StrConnection As String
Dim Conn As OleDbConnection
dbName = My.Settings("dbName")
StrConnection = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & dbName
Conn = New OleDbConnection(StrConnection)
Return Conn
End Function
'在数据库中插入一行数据
Public Sub Add()
Dim Conn As OleDbConnection = GetConnection()
Try
Conn.Open()
Dim Sql As String = "INSERT INTO Users(name,password) VALUES (@name,@password)"
Dim Cmd As OleDbCommand = New OleDbCommand(Sql, Conn)
Dim P1 As OleDbParameter = New OleDbParameter("@name", Me.Name)
Dim P2 As OleDbParameter = New OleDbParameter("@password", Me.Password)
Cmd.Parameters.Add(P1)
Cmd.Parameters.Add(P2)
Cmd.ExecuteNonQuery()
Catch ex As Exception
Conn.Close()
End Try
End Sub
'获取数据库中的全部数据
Public Function GetAll() As DataTable
Dim Conn As OleDbConnection = GetConnection()
Dim Sql As String = "SELECT * FROM Users"
Dim myDataAdapter As OleDbDataAdapter = New OleDbDataAdapter(Sql, Conn)
Dim Cmd As OleDbCommandBuilder = New OleDbCommandBuilder(myDataAdapter)
Dim Dt As DataTable = New DataTable()
myDataAdapter.Fill(Dt)
Return Dt
End Function
End Class
这是窗体Form1的全部代码，窗体上有一个 DataGridView 控件，用以显示数据库的内容，并且在程序启动的时候就把数据加载进去。
- VB.NET code
Imports dbFunction
Public Class Form1
Dim UserData As UserPermission
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
DataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect
UserData = New UserPermission()
DataGridView1.DataSource = UserData.GetAll()
End Sub
'保存
Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click
UserData.Name = txtName.Text.Trim
UserData.Password = txtPassword.Text.Trim
UserData.Add()
DataGridView1.DataSource = UserData.GetAll()
End Sub
End Class
------解决方案--------------------
估计是你操作没完成。
- VB.NET code
Catch ex As Exception
Conn.Close()
End Try