Question

我有DataGridview显示数据，TextBox允许我使用SQL查询过滤BindingSource以根据输入字符串显示数据。除了我已经过滤DataGridView我正在重置它的计时器功能以便再次显示所有数据之外，这一切都正常工作。计时器设置为1000ms，因此它会显示过滤后的结果一秒钟，然后还原。

继承我的代码：

Imports System.Data.OleDb

Public Class Form1

    Dim duraGadgetDB As String = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source = C:\Users\Dave\Documents\duraGadget.mdb;"
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim sql As String = "SELECT * FROM duragadget"
        Dim connection As New OleDbConnection(duraGadgetDB)
        Dim dataadapter As New OleDbDataAdapter(sql, connection)
        Dim ds As New DataSet()
        connection.Open()
        dataadapter.Fill(ds, "dura")
        connection.Close()
        DataGridView1.DataSource = ds
        DataGridView1.DataMember = "dura"
        DataGridView1.Columns(5).Width = 300 
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        insert.Show()
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Dim currentRowID As Integer
        Dim scrollPosition As Integer = DataGridView1.FirstDisplayedScrollingRowIndex
        Try
            If DataGridView1.CurrentRow IsNot Nothing Then

                currentRowID = DataGridView1.CurrentRow.Index

                Dim sql As String = "SELECT * FROM duragadget"
                Dim connection As New OleDbConnection(duraGadgetDB)
                Dim dataadapter As New OleDbDataAdapter(sql, connection)
                Dim ds As New DataSet()
                connection.Open()
                dataadapter.Fill(ds, "dura")
                connection.Close()
                DataGridView1.DataSource = ds
                DataGridView1.DataMember = "dura"
                DataGridView1.CurrentCell = DataGridView1.Item(1, currentRowID)
            End If
        Catch ex As Exception

        End Try
        DataGridView1.FirstDisplayedScrollingRowIndex = scrollPosition
    End Sub

    Private Sub txtSearchOnSku_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txtSearchOnSku.TextChanged
        Dim currentRowID As Integer
        Dim scrollPosition As Integer = DataGridView1.FirstDisplayedScrollingRowIndex
        Try
            If DataGridView1.CurrentRow IsNot Nothing Then
                currentRowID = DataGridView1.CurrentRow.Index
                Dim sql As String = "SELECT * FROM duragadget"
                Dim connection As New OleDbConnection(duraGadgetDB)
                Dim dataadapter As New OleDbDataAdapter(sql, connection)
                Dim ds As New DataSet()
                Dim dsView As New DataView
                Dim bs As New BindingSource()
                connection.Open()
                dataadapter.Fill(ds, "dura")
                connection.Close()
                dsView = ds.Tables(0).DefaultView
                bs.DataSource = dsView
                bs.Filter = "skuNo LIKE'" & txtSearchOnSku.Text & "*'"
                DataGridView1.DataSource = bs
                DataGridView1.CurrentCell = DataGridView1.Item(1, currentRowID)
            End If
        Catch ex As Exception
        End Try
        DataGridView1.FirstDisplayedScrollingRowIndex = scrollPosition
    End Sub
End Class

谁能告诉我如何阻止这种情况发生？

Answer 1

假设您的意思是，如果您在文本框中输入了一个值来过滤结果，那么您就不希望计时器触发并取消过滤...

您也可以在Timer1_Tick例程中检查TextBox的内容;

If txtSearchOnSku.Text <> "" Then Exit Sub

或者你可以在txtSearchOnSku_TextChanged例程中禁用你的计时器;

If txtSearchOnSku.Text <> "" Then 
   Timer1.Stop
Else
   Timer1.Start
End If

或者，如果您想根据搜索每秒更新一次结果，可以在Timer1_Tick例程中包含过滤代码。

作为一个快速点，你有很多重复的代码。将重复的代码重构为另一个子代值可能是值得的。

DataGridView和BindingSource计时器问题

1 个答案: