Question

我正在尝试优化我前一段时间编写的应用程序的输出，尽管我在很多方面取得了很多成就，但我仍在努力加快将listview的结果导出到.xlsx文件的功能。

我正在使用Interop来做，如下所示：

Imports Excel = Microsoft.Office.Interop.Excel
Imports System
Imports System.IO
Imports System.Data.OleDb
Imports System.Threading
Imports System.Linq
Imports System.Data.SqlClient

这是导出listview中数据的函数：

Private Function ExportListViewTab5ToXLSxFile(ByRef FileNameWithoutExtension As String, ByRef OutputDir As String) As Boolean

        Try
            Dim objExcel As Excel.Application = New Excel.Application
            Dim bkWorkBook As Excel.Workbook
            Dim shWorkSheet As Excel.Worksheet
            Dim i As Integer
            Dim j As Integer

            objExcel = New Excel.Application
            bkWorkBook = objExcel.Workbooks.Add
            shWorkSheet = CType(bkWorkBook.ActiveSheet, Excel.Worksheet)

            For i = 0 To lvObjectsTab5.Columns.Count - 1
                shWorkSheet.Cells(1, i + 1) = lvObjectsTab5.Columns(i).Text
            Next
            For i = 0 To lvObjectsTab5.Items.Count - 1
                For j = 0 To lvObjectsTab5.Items(i).SubItems.Count - 1
                    shWorkSheet.Cells(i + 2, j + 1) = lvObjectsTab5.Items(i).SubItems(j).Text
                Next
            Next

            shWorkSheet.Columns.AutoFit()

            Try

                '/////////////////
                '// Save report //
                '/////////////////
                Try
                    shWorkSheet.SaveAs(OutputDir & "\" & FileNameWithoutExtension & ".xlsx")
                Catch ex As Exception
                    MessageBox.Show("A exportação do relatório foi cancelada pelo usuário!", "Exportação cancelada!", MessageBoxButtons.OK, MessageBoxIcon.Error)
                    Return False
                End Try

                '///////////////////////////////////
                '// Close EXCEL.EXE COM processes //
                '///////////////////////////////////

                bkWorkBook.Close()
                objExcel.Workbooks.Close()
                NAR(bkWorkBook)
                objExcel.Quit()
                NAR(objExcel)

                '//////////////////////////
                '// Open report in Excel //
                '//////////////////////////

                Process.Start(OutputDir & "\" & FileNameWithoutExtension & ".xlsx")
                Return True

            Catch ex As Exception
                MessageBox.Show("Falha ao exportar o arquivo '" & FileNameWithoutExtension & ".xlsx' para '" & OutputDir & "'", "Falha ao exportar relatório!" & vbCrLf & vbCrLf & _
                                "Detalhes do erro:" & vbCrLf & vbCrLf & _
                                ex.ToString, MessageBoxButtons.OK, MessageBoxIcon.Error)
                Return False
            End Try
        Catch ex As Exception
            MessageBox.Show("Falha ao exportar o arquivo '" & FileNameWithoutExtension & ".xlsx' para '" & OutputDir & "'", "Falha ao exportar relatório!" & vbCrLf & vbCrLf & _
                            "Detalhes do erro:" & vbCrLf & vbCrLf & _
                            ex.ToString, MessageBoxButtons.OK, MessageBoxIcon.Error)
            Return False
        End Try

    End Function

listview包含10列，导出2000行需要4分钟。太多了。我用谷歌搜索了几个小时，搜索了几个性能问题的例子，但我发现的所有例子都与我的相似。

有人可以指导我如何使用.NET代码提高函数的性能吗？在典型情况下，此列表视图列出了15000行。我限制在2000，所以对用户来说不那么痛苦。

有什么建议吗？

提前致谢，丹尼尔

Answer 1

尝试一次性将所有值应用为范围。像这样的东西可能会这样做。

dim Values(lvObjectsTab5.Items.Count, lvObjectsTab5.Items(i).SubItems.Count) as object
dim Range as Excel.Range = shWorkSheet.Range("A1","J" & (lvObjectsTab5.Items.Count+ 1))

For i = 0 To lvObjectsTab5.Columns.Count - 1
    Values(0, i ) = lvObjectsTab5.Columns(i).Text
Next

For i = 0 To lvObjectsTab5.Items.Count - 1
        For j = 0 To lvObjectsTab5.Items(i).SubItems.Count - 1
            Values(i+1,j) = lvObjectsTab5.Items(i).SubItems(j).Text
        Next
Next
Range.value = Values

编辑：在值矩阵中插入列标题。

将ListView导出到Excel - 苦苦挣扎的表现

1 个答案: