Question

我有一个带有多个datagridviews的应用程序，现在，超过260行，我的数据网格填充速度太慢，我不知道如何缩短时间。

这是我的代码：

Public cs As String = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & Application.StartupPath & "\BD_Estaleiro.accdb"

Public con As New OleDbConnection(cs)

Public cmd As OleDbCommand

Public dr As OleDbDataReader

Public query As String

读者功能：

    Public Function executar_query_Reader(ByVal Instrucao As String) As OleDb.OleDbDataReader
    Dim datareader As OleDbDataReader = Nothing 

    cmd = New OleDbCommand(Instrucao, con) 
    Try
        If con.State = ConnectionState.Open Then
            con.Close()
        End If
        con.Open()
        datareader = cmd.ExecuteReader 

    Catch ex As Exception
        MessageBox.Show(ex.Message) 'mensagem de erro, se aplicavel
    Finally

    End Try

    Return datareader 'retornar os dados atraves da variavel datareader
End Function

填充数据网格：

Public Sub carregar_saidas(ByVal DG As DataGridView)

    n_rows = 0
    DG.Rows.Clear()
    query = "Select * from tbl_saidas as s, tbl_produtos as p Where s.Produto=p.Produto Order By s.Data DESC"
    dr = executar_query_Reader(query)
    While dr.Read
        n_rows += 1
        Dim n As Integer = DG.Rows.Add()
        DG.Rows.Item(n).Cells(0).Value = dr("ID")
        DG.Rows.Item(n).Cells(1).Value = dr("s.Produto")
        DG.Rows.Item(n).Cells(2).Value = dr("s.Quantidade")
        DG.Rows.Item(n).Cells(3).Value = dr("Unidade")
        DG.Rows.Item(n).Cells(4).Value = dr("Obra")
        DG.Rows.Item(n).Cells(5).Value = Format(dr("Data"), "dd/MM/yyyy")
        DG.Rows.Item(n).Cells(6).Value = Format$(CSng(dr("Valor_uni")), "###,####,##0.00") & " €"
        DG.Rows.Item(n).Cells(7).Value = Format$(CSng(dr("Total")), "###,####,##0.00") & " €"
    End While
    con.Close()
End Sub

感谢您的帮助

Answer 1

您希望绑定到网格中，而不是添加单独的行和列：

gcc-4.9.3

您需要在DataGridView上定义列以映射数据读取器中的字段。

您还应该考虑修改Public Sub carregar_saidas(ByVal DG As DataGridView) Dim query As String = "Select * from tbl_saidas as s, tbl_produtos as p Where s.Produto=p.Produto Order By s.Data DESC" Dim dr As OleDbDataReader = executar_query_Reader(query) DG.DataSource = dr End Sub方法以支持参数化查询。

Access数据库太慢填充DatagridView

1 个答案: