SQL导出到Excel循环中缺少前导零

Question

新的VB程序员在这里。 我正在使用以下方法将SQL表导出到Excel文件。 但是，当我在excel中创建文件时，主键的前导零丢失了，因为它们被转换为数字而不是文本。 这是由于信息来自数据表到excel。 我想知道如何才能保持我的领先零。

仅供参考-我的主键是6位数字，只有少数数字的开头缺少单个0。 在第一列之后，有许多其他列和行被放入excel文件，它们都可以正常工作。 这只是我需要以某种方式更改格式的第一列主键。

另外，我正在使用此excel文件将其上传到SQL，并且某些主键上缺少的0使我的程序创建了一条新记录。

我以为主要的变化可能会在这里发生，但我不知道该怎么做：

                'Export the Columns to excel file
                For Each dc In datatableMain.Columns
                    colIndex = colIndex + 1
                    oSheet.Cells(1, colIndex) = dc.ColumnName
                Next

                For Each dr In datatableMain.Rows
                    rowIndex = rowIndex + 1
                    colIndex = 1

                    For Each dc In datatableMain.Columns
                        colIndex = colIndex + 1
                        oSheet.Cells(rowIndex + 1, colIndex) = dr(dc.ColumnName)
                    Next
                Next

完整代码如下：

Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click

        Dim dataAdapter As New SqlClient.SqlDataAdapter()
        Dim dataSet As New DataSet
        Dim command As New SqlClient.SqlCommand
        Dim datatableMain As New System.Data.DataTable()
        Dim connection As New SqlClient.SqlConnection


        connection.ConnectionString = "Server=myserver;Database=mydatabase;User Id=xxxx;Password=xxxxx"
        command.Connection = connection
        command.CommandType = CommandType.Text
        'You can use any command select
        command.CommandText = "Select * from MYTABLE"
        dataAdapter.SelectCommand = command


        Dim f As FolderBrowserDialog = New FolderBrowserDialog
        Try
            If f.ShowDialog() = DialogResult.OK Then
                'This section help you if your language is not English.
                System.Threading.Thread.CurrentThread.CurrentCulture = _
                System.Globalization.CultureInfo.CreateSpecificCulture("en-US")
                Dim oExcel As Excel.Application
                Dim oBook As Excel.Workbook
                Dim oSheet As Excel.Worksheet
                oExcel = CreateObject("Excel.Application")
                oBook = oExcel.Workbooks.Add(Type.Missing)
                oSheet = oBook.Worksheets(1)

                Dim dc As System.Data.DataColumn
                Dim dr As System.Data.DataRow
                Dim colIndex As Integer = 0
                Dim rowIndex As Integer = 0

                'Fill data to datatable
                connection.Open()

                dataAdapter.Fill(datatableMain)
                connection.Close()

                'Export the Columns to excel file
                For Each dc In datatableMain.Columns
                    colIndex = colIndex + 1
                    oSheet.Cells(1, colIndex) = dc.ColumnName
                Next

                For Each dr In datatableMain.Rows
                    rowIndex = rowIndex + 1
                    colIndex = 1

                    For Each dc In datatableMain.Columns
                        colIndex = colIndex + 1
                        oSheet.Cells(rowIndex + 1, colIndex) = dr(dc.ColumnName)
                    Next
                Next

                'Set final path
                Dim fileName As String = "\" + fname.Text + ".xlsx"
                Dim finalPath = f.SelectedPath + fileName
                txtPath.Text = finalPath
                oSheet.Columns.AutoFit()
                'Save file in final path
                oBook.SaveAs(finalPath, Excel.XlFileFormat.xlOpenXMLWorkbook, Type.Missing, _
                Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlExclusive, _
                Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing)

                'Release the objects
                ReleaseObject(oSheet)
                oBook.Close(False, Type.Missing, Type.Missing)
                ReleaseObject(oBook)
                oExcel.Quit()
                ReleaseObject(oExcel)
                'Some time Office application does not quit after automation: 
                'so i am calling GC.Collect method.
                GC.Collect()

                MessageBox.Show("Exported!")

            End If
        Catch ex As Exception
            MessageBox.Show(ex.Message, "Warning", MessageBoxButtons.OK)
        End Try
    End If
End Sub
Private Sub ReleaseObject(ByVal o As Object)
    Try
        While (System.Runtime.InteropServices.Marshal.ReleaseComObject(o) > 0)
        End While
    Catch
    Finally
        o = Nothing
    End Try
End Sub

Answer 1

实际上，我大约在10分钟前遇到了类似的问题！ 我需要从一本书到另一本书获得30左右的数字，这使所有内容都泛滥成灾。 在写入单元格之前，请尝试设置列的格式。 我的代码是Worksheets(i).Range("D:D").NumberFormat = "@"这将告诉Excel“按原样”对数据进行Worksheets(i).Range("D:D").NumberFormat = "@"而不是尝试猜测您想要的内容。

Answer 2

我发现了这个问题，希望在我拥有的通用函数中解决同一问题，该函数已由我创建的几个程序使用。 由于数据源种类繁多，我无法硬编码设置NumberFormat列。 为了解决这个问题，我利用了循环，我必须输出列标题。 下面的代码供那些需要更多动态解决方案的用户使用。 注意，在同一解决方案中，有几个对“ EL”的引用，它们是一个自定义错误记录对象的实例，可以被忽略/修改：

''' <summary>
''' Function to take a data table and output its contents to an Excel spreadsheet. Returns a string with any errors (Nothing if successful)
''' </summary>
''' <param name="D">The datatable to be output</param>
''' <param name="epath">The full file path to log errors to</param>
''' <param name="SAName">The full file path to save the created Excel workbook to</param>
''' <param name="Parent">The function calling for data to be output</param>
''' <returns></returns>
''' <remarks></remarks>
Public Function ResOut(ByVal D As DataTable, ByVal epath As String, ByVal SAName As String, ByVal Parent As String) As String
    '
    Dim res As String = ""
    Dim E As New Microsoft.Office.Interop.Excel.Application
    Dim wb As Microsoft.Office.Interop.Excel.Workbook = Nothing
    Dim ws As Microsoft.Office.Interop.Excel.Worksheet = Nothing
    Dim x As Long = 0
    Dim f As Long = 1
    Dim Rng As Microsoft.Office.Interop.Excel.Range = Nothing
    Dim q As String
    Dim Str_Columns As New List(Of String) 'Holds the list of column letters that need forced to Text format in order to retain leading zeroes in the data 
    'that will be placed there
    'Check that the passed in table has data
    If D.Rows.Count = 0 Then
        res = "No data was returned by " & Parent
    End If

    If res = "" Then
        'Create a workbook for the data and capture the workbook and sheet for ease of reference
        Try
            wb = E.Workbooks.Add
            ws = wb.Worksheets(1)

            'Define the range
            q = ColNumToStr(D.Columns.Count, epath)
            Rng = ws.Range("A2:" & q & D.Rows.Count + 1)
        Catch ex As Exception
            res = "Encountered an error while creating the new workbook to export the results to. No data can be returned."
            EL.AddErr(res & " ResOut was called by " & Parent & ". Error Details: " & ex.Message, epath)
        End Try

        'Fill in headers
        If res = "" Then
            Try
                For Each c As DataColumn In D.Columns
                    ws.Range("A1").Offset(0, x).Value = c.ColumnName
                    x = x + 1
                Next
            Catch ex As Exception
                res = "Encountered an error while filling in the column headers. This will prevent any data from being returned."
                EL.AddErr(res & " ResOut was called by " & Parent & ". Error Details: " & ex.Message, epath)
            End Try
        End If

        'Setup the step & frequency for the Step Progress bar
        'Dim t() As Long = s.StatSetup(QR.Rows.Count, 58, "Query Runner\ResOut\" & QName, Replace(My.Settings.EPath, "<user>", Environment.UserName) & DStamp() & " Query Scheduler Log.txt")
        'f = t(0)
        'SProg.Step = t(1)

        'Create the array
        Dim OArr(D.Rows.Count, x) As Object

        'Convert the datatable to a 2D array
        If res = "" Then
            Try
                'Fill it
                x = 0
                For r As Long = 0 To D.Rows.Count - 1 Step 1
                    Dim dr As DataRow = D.Rows(r)

                    For c As Integer = 0 To D.Columns.Count - 1 Step 1
                        OArr(r, c) = dr.Item(c).ToString

                        'Check if this item is a # with leading zeroes (making sure we haven't already added the column to the list of such columns)
                        If Not (Str_Columns.Contains(ColNumToStr(c + 1, epath))) And Strings.Left(dr.Item(c), 1) = "0" Then
                            Str_Columns.Add(ColNumToStr(c + 1, epath))
                        End If 'else the column is in the list already or the item does not dictate it's inclusion
                    Next
                    x = x + 1
                Next
            Catch ex As Exception
                res = "Encountered an error while outputing the " & x + 1 & "-th record of " & D.Rows.Count & ". No data will be output."
                EL.AddErr(res & " ResOut was called by " & Parent & ". Error Details: " & ex.Message, epath)
            End Try
        End If

        'output the array to the target range
        If res = "" Then
            'First force Text format where needed to retain leading zeroes
            Try
                For Each c As String In Str_Columns
                    q = c
                    ws.Range(c & ":" & c).NumberFormat = "@"
                Next
            Catch ex As Exception
                res = "Encountered an error while changing column " & q & " to TEXT in order to retain leading zeroes in the " & ws.Range(q & 1).Value & "data."
                E.Visible = True
                wb.Activate()
                EL.AddErr(res & " ResOut was called by " & Parent & ". Error Details: " & ex.Message & Chr(10) & Chr(10) & "Inner Exception: " & ex.InnerException.Message _
                          , epath)
            End Try

            Try
                Rng.Value = OArr

                'Save the workbook
                wb.SaveAs(SAName)
                wb.Close(SaveChanges:=False)
            Catch ex As Exception
                res = "Encountered an error during the export of the results. Some data may have been exported. Review the contents of the Excel workbook that will " _
                    & "be visible following this message for more details."
                E.Visible = True
                wb.Activate()
                EL.AddErr(res & " ResOut was called by " & Parent & ". Error Details: " & ex.Message, epath)
            End Try
        Else
            'Close the workbook without saving
            wb.Close(SaveChanges:=False)
        End If

        'Cleanup the application
        Try
            E.Quit()
            System.Runtime.InteropServices.Marshal.ReleaseComObject(E)
            E = Nothing
            wb = Nothing
            ws = Nothing
            Rng = Nothing
            OArr = Nothing
            f = Nothing
            x = Nothing
        Catch ex As Exception
            EL.AddErr("Encountered an error while cleaning up the resources used in JMLib\ResOut. ResOut was called by " & Parent & ". Error Details: " & ex.Message, epath)
        End Try
    End If

    Return res
End Function