当我获取DataGridView
的数据时,我的表单会冻结,直到While
循环完成,但我的滚动条工作正常。我试着打电话给Application.DoEvents();
,但这也不起作用。
如果我在线程中获取数据,那么我的表单不会冻结,但滚动条会在While
完成后禁用并且不起作用。我尝试了BackgroundWorker
,但滚动条在使用时也有问题。
Private Sub dg()
myth = New Threading.Thread(AddressOf dgd)
myth.IsBackground = True
myth.Start()
End Sub
Private Sub dgd()
Dim x As Integer
If DataGridView1.Rows.Count = 0 Then x = 0 Else x = DataGridView1.Rows.Count
Try
Dim conn35a As New OleDbConnection("connstring")
Dim cmd35a As New OleDbCommand
cmd35a.CommandText = "Select count(*) from asd where downur Is Null"
cmd35a.CommandType = CommandType.Text
cmd35a.Connection = conn35a
conn35a.Open()
Dim returnValueaa As Integer = cmd35a.ExecuteScalar()
conn35a.Close()
Dim komut As String = "Select * from asd where downur Is Null"
Dim conn2 As New OleDbConnection("connstring")
conn2.Open()
Dim cmd2 As New OleDbCommand(komut, conn2)
Dim dr2 As OleDbDataReader = cmd2.ExecuteReader
If dr2.HasRows Then
While dr2.Read
Dim conn35 As New OleDbConnection("connstring")
Dim cmd35 As New OleDbCommand
cmd35.CommandText = "select count(*) from grid where ur = '" + dr2.Item("ur").ToString + "'"
cmd35.CommandType = CommandType.Text
cmd35.Connection = conn35
conn35.Open()
Dim returnValuea = cmd35.ExecuteScalar()
conn35.Close()
If returnValuea = 0 Then
DataGridView1.Rows.Add()
DataGridView1.Rows.Item(x).Cells(0).Value = x + 1
DataGridView1.Rows.Item(x).Cells(4).Value = "ID"
DataGridView1.Rows.Item(x).Cells(5).Value = dr2.Item("ur").ToString
DataGridView1.Rows.Item(x).Cells(6).Value = dr2.Item("ch").ToString
DataGridView1.Rows.Item(x).Cells(7).Value = dr2.Item("ti").ToString
DataGridView1.Rows.Item(x).Cells(8).Value = ".."
Dim client2 As New WebClient
Dim url As String = dr2.Item("pic").ToString
DataGridView1.Rows.Item(x).Cells(12).Value = New Bitmap(New MemoryStream(client2.DownloadData(url)))
DataGridView1.Rows.Item(x).Cells(13).Value = dr2.Item("vi")
DataGridView1.Rows.Item(x).Cells(14).Value = dr2.Item("su").ToString()
Dim con4 As New OleDbConnection("connstring")
con4.Open()
Dim cmd5 = New OleDbCommand("INSERT INTO grid (ur) VALUES (@ur)", con4)
cmd5.CommandType = CommandType.Text
cmd5.Parameters.Add("@ur", OleDbType.VarChar, 500).Value = dr2.Item("ur").ToString
cmd5.ExecuteNonQuery()
con4.Close()
x += 1
End If
End While
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
答案 0 :(得分:0)
我遇到了同样的问题。
我通过删除Thread并直接调用方法来解决这个问题