Microsoft KB Archive/306022

From BetaArchive Wiki

Article ID: 306022

Article Last Modified on 1/17/2007



APPLIES TO

  • Microsoft Excel 2002 Standard Edition
  • Microsoft Visual Basic .NET 2002 Standard Edition
  • Microsoft .NET Framework 1.1 Service Pack 1



This article was previously published under Q306022

For a Microsoft Visual C# .NET version of this article, see 306023.

SUMMARY

This step-by-step article describes several methods for transferring data to Excel 2002 from a Visual Basic .NET program. This article also presents the advantages and disadvantages of each method so that you can select the solution that works best for your situation.

Overview

The technique that is used most frequently to transfer data to an Excel workbook is Automation. With Automation, you can call methods and properties that are specific to Excel tasks. Automation gives you the greatest flexibility for specifying the location of your data in the workbook, and the ability to format the workbook and make various settings at run time.

With Automation, you can use several techniques to transfer your data:

  • Transfer data cell by cell.
  • Transfer data in an array to a range of cells.
  • Transfer data in an ADO recordset to a range of cells by using the CopyFromRecordset method.
  • Create a QueryTable object on an Excel worksheet that contains the result of a query on an ODBC or OLEDB data source.
  • Transfer data to the clipboard, and then paste the clipboard contents into an Excel worksheet.

You can also use several methods that do not necessarily require Automation to transfer data to Excel. If you are running a server-side program, this can be a good approach for taking the bulk of data processing away from your clients.

The following approaches may be used to transfer your data without Automation:

  • Transfer your data to a tab- or comma-delimited text file that Excel can later parse into cells on a worksheet.
  • Transfer your data to a worksheet using ADO.NET.
  • Transfer XML data to Excel (version 2002 only) to provide data that is formatted and arranged into rows and columns.

Techniques

Use Automation to transfer data cell by cell

With Automation, you can transfer data to a worksheet one cell at a time, as follows.

        Dim oExcel As Object
        Dim oBook As Object
        Dim oSheet As Object

        'Start a new workbook in Excel.
        oExcel = CreateObject("Excel.Application")
        oBook = oExcel.Workbooks.Add

        'Add data to cells of the first worksheet in the new workbook.
        oSheet = oBook.Worksheets(1)
        oSheet.Range("A1").Value = "Last Name"
        oSheet.Range("B1").Value = "First Name"
        oSheet.Range("A1:B1").Font.Bold = True
        oSheet.Range("A2").Value = "Doe"
        oSheet.Range("B2").Value = "John"

        'Save the Workbook and quit Excel.
        oBook.SaveAs(sSampleFolder & "Book1.xls")
        oSheet = Nothing
        oBook = Nothing
        oExcel.Quit()
        oExcel = Nothing
        GC.Collect()
                

Transferring data cell by cell can be an acceptable approach if there is not much data to transfer. You have the flexibility to put data anywhere in the workbook and can format the cells conditionally at run time. However, this approach is not recommended if you have a lot of data to transfer to an Excel workbook. Each Range object that you acquire at run time results in an interface request. Therefore, transferring data in this manner can be slow.
Additionally, Microsoft Windows 95, Microsoft Windows 98, and Microsoft Windows Millennium Edition (Me) have a 64 KB limitation on interface requests. If you have 64 KB or more of interface requests, the Automation server (Excel) may stop responding, or you may receive error messages that indicate low memory. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

216400 Cross-process COM Automation can hang client application on Win95/98


Again, transferring data cell by cell is acceptable only for small amounts of data. If you must transfer large data sets to Excel, consider using one of the other approaches that are discussed in this article to transfer data in bulk.

For more information, and for an example of how to automate Excel with Visual Basic .NET, click the following article number to view the article in the Microsoft Knowledge Base:

301982 How to automate Microsoft Excel from Visual Basic .NET


Use Automation to transfer an array of data to a range on a worksheet

An array of data can be transferred to a range of multiple cells at the same time, as follows.

        Dim oExcel As Object
        Dim oBook As Object
        Dim oSheet As Object

        'Start a new workbook in Excel.
        oExcel = CreateObject("Excel.Application")
        oBook = oExcel.Workbooks.Add

        'Create an array with 3 columns and 100 rows.
        Dim DataArray(99, 2) As Object
        Dim r As Integer
        For r = 0 To 99
            DataArray(r, 0) = "ORD" & Format(r + 1, "0000")
            DataArray(r, 1) = Rnd() * 1000
            DataArray(r, 2) = DataArray(r, 1) * 0.07
        Next

        'Add headers to the worksheet on row 1.
        oSheet = oBook.Worksheets(1)
        oSheet.Range("A1").Value = "Order ID"
        oSheet.Range("B1").Value = "Amount"
        oSheet.Range("C1").Value = "Tax"

        'Transfer the array to the worksheet starting at cell A2.
        oSheet.Range("A2").Resize(100, 3).Value = DataArray

        'Save the Workbook and quit Excel.
        oBook.SaveAs(sSampleFolder & "Book2.xls")
        oSheet = Nothing
        oBook = Nothing
        oExcel.Quit()
        oExcel = Nothing
        GC.Collect()
                

If you transfer data by using an array instead of cell by cell, you can realize an enormous performance gain with a lot of data. Consider this line from the earlier code, which transfers data to 300 cells in the worksheet.

        oSheet.Range("A2").Resize(100, 3).Value = DataArray
                

This line represents two interface requests: one for the Range object that the Range method returns, and another for the Range object that the Resize method returns. In contrast, transferring the data cell by cell requires requests for 300 interfaces to Range objects. Whenever possible, you can benefit from transferring your data in bulk and reducing the number of interface requests you make.

Use Automation to transfer an ADO recordset to a worksheet range

The object models for Excel 2000 and Excel 2002 provide the CopyFromRecordset method for transferring an ADO recordset to a range on a worksheet. The following code illustrates how to automate Excel to transfer the contents of the Orders table in the Northwind sample database by using the CopyFromRecordset method.

        'Create a Recordset from all the records in the Orders table.
        Dim sNWind As String
        Dim conn As New ADODB.Connection()
        Dim rs As ADODB.Recordset
        conn.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _
            sNorthwind & ";")
        conn.CursorLocation = ADODB.CursorLocationEnum.adUseClient
        rs = conn.Execute("Orders", , ADODB.CommandTypeEnum.adCmdTable)

        'Create a new workbook in Excel.
        Dim oExcel As Object
        Dim oBook As Object
        Dim oSheet As Object
        oExcel = CreateObject("Excel.Application")
        oBook = oExcel.Workbooks.Add
        oSheet = oBook.Worksheets(1)

        'Transfer the field names to Row 1 of the worksheet:
        'Note: CopyFromRecordset copies only the data and not the field
        '      names, so you can transfer the fieldnames by traversing the
        '      fields collection.
        Dim n As Int32
        For n = 1 To rs.Fields.Count
            oSheet.Cells(1, n).Value = rs.Fields(n - 1).Name
        Next

        'Transfer the data to Excel.
        oSheet.Range("A2").CopyFromRecordset(rs)

        'Save the workbook and quit Excel.
        oBook.SaveAs(sSampleFolder & "Book3.xls")
        oSheet = Nothing
        oBook = Nothing
        oExcel.Quit()
        oExcel = Nothing
        GC.Collect()

        'Close the connection
        rs.Close()
        conn.Close()
                

Note CopyFromRecordset works only with ADO Recordset objects. A DataSet that you create by using ADO.NET cannot be used with the CopyFromRecordset method. Several examples in the sections that follow demonstrate how to transfer data to Excel with ADO.NET.

Use Automation to create a QueryTable object on a worksheet

A QueryTable object represents a table that is built from data that is returned from an external data source. While you automate Excel, you can create a QueryTable by providing a connection string to an OLEDB or an ODBC data source and a SQL string. Excel generates the recordset and inserts the recordset into the worksheet at the location that you specify. Using QueryTable objects offers the following advantages over the CopyFromRecordset method:

  • Excel handles the creation of the recordset and its placement into the worksheet.
  • The query can be saved with the QueryTable object so that it can be refreshed later to obtain an updated recordset.
  • When a new QueryTable is added to your worksheet, you can specify that data already existing in cells on the worksheet be shifted to fit the new data (see the RefreshStyle property for details).

The following code demonstrates how to automate Excel 2000 or 2002 to create a new QueryTable in an Excel worksheet by using data from the Northwind sample database.

        'Create a new workbook in Excel.
        Dim oExcel As Object
        Dim oBook As Object
        Dim oSheet As Object
        oExcel = CreateObject("Excel.Application")
        oBook = oExcel.Workbooks.Add
        oSheet = oBook.Worksheets(1)

        'Create the QueryTable object.
        Dim oQryTable As Object
        oQryTable = oSheet.QueryTables.Add( _
        "OLEDB;Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _
            sNorthwind & ";", oSheet.Range("A1"), _
            "Select * from Orders")
        oQryTable.RefreshStyle = 2 ' xlInsertEntireRows = 2
        oQryTable.Refresh(False)

        'Save the workbook and quit Excel.
        oBook.SaveAs(sSampleFolder & "Book4.xls")
        oQryTable = Nothing
        oSheet = Nothing
        oBook = Nothing
        oExcel.Quit()
        oExcel = Nothing
                

Use the Clipboard

You can use the Clipboard to transfer data to a worksheet. To paste data into multiple cells on a worksheet, you can copy a string in which columns are delimited by tab characters, and rows are delimited by carriage returns. The following code illustrates how Visual Basic .NET uses the Clipboard to transfer data to Excel.

        'Copy a string to the Clipboard.
        Dim sData As String
        sData = "FirstName" & vbTab & "LastName" & vbTab & "Birthdate" & vbCr _
            & "Bill" & vbTab & "Brown" & vbTab & "2/5/85" & vbCr _
            & "Joe" & vbTab & "Thomas" & vbTab & "1/1/91"
        System.Windows.Forms.Clipboard.SetDataObject(sData)

        'Create a workbook in Excel.
        Dim oExcel As Object
        Dim oBook As Object
        oExcel = CreateObject("Excel.Application")
        oBook = oExcel.Workbooks.Add

        'Paste the data.
        oBook.Worksheets(1).Range("A1").Select()
        oBook.Worksheets(1).Paste()

        'Save the workbook and quit Excel.
        oBook.SaveAs(sSampleFolder & "Book5.xls")
        oBook = Nothing
        oExcel.Quit()
        oExcel = Nothing
        GC.Collect()
                

Create a delimited text file that Excel can parse into rows and columns

Excel can open tab-delimited files or comma-delimited files and correctly parse the data into cells. You can use this feature when you want to transfer a lot of data to a worksheet while using little, if any, Automation. This may be a good approach for a client-server program, because the text file can be generated server-side. You can then open the text file at the client, using Automation where it is appropriate.

The following code illustrates how to generate a tab-delimited text file from data that is read with ADO.NET.

        'Connect to the data source.
        Dim objConn As New System.Data.OleDb.OleDbConnection( _
            "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sNorthwind & ";")
        objConn.Open()

        'Execute a command to retrieve all records from the Employees table.
        Dim objCmd As New System.Data.OleDb.OleDbCommand( _
            "Select * From Employees", objConn)
        Dim objReader As System.Data.OleDb.OleDbDataReader
        objReader = objCmd.ExecuteReader()

        'Read the records in the dataset and write select fields to the 
        'output file.
        FileOpen(1, sSampleFolder & "Book6.txt", OpenMode.Output)
        Dim i As Integer, s As String
        While objReader.Read()
            'Loop through first 6 fields and concatenate
            'each field, separated by a tab, into s variable.
            s = ""
            For i = 0 To 5
                If Not objReader.IsDBNull(i) Then
                    If i = 0 Then 'field 1 is EmployeeId
                        s = s & objReader.GetInt32(i).ToString
                    ElseIf i = 5 Then 'field 6 is BirthDate
                        s = s & objReader.GetDateTime(i)
                    Else 'field is a text field
                        s = s & objReader.GetString(i)
                    End If
                End If
                s = s & Microsoft.VisualBasic.ControlChars.Tab
            Next
            PrintLine(1, s)
        End While
        FileClose(1)

        'Close the reader and the connection.
        objReader.Close()
        objConn.Close()
                

No Automation was used in the previous code. However, you can use minimal Automation to open the text file and save the file in the Excel workbook format, as follows.

        'Create a new instance of Excel.
        Dim oExcel As Object
        oExcel = CreateObject("Excel.Application")

        'Open the text file and save it in the Excel workbook format.
        oExcel.Workbooks.OpenText(sSampleFolder & "Book6.txt", _
            , , , -4142, , True) 'xlTextQualifierNone=-4142

        oExcel.ActiveWorkbook.SaveAs(sSampleFolder & "Book6.xls", _
            -4143) 'xlWorkbookNormal = -4143

        'Quit Excel.
        oExcel.Quit()
        oExcel = Nothing
        GC.Collect()
                

Transfer data to a worksheet by using ADO.NET

You can use the Microsoft Jet OLE DB provider to add records to a table in an existing Excel workbook. A "table" in Excel is merely a range of cells; the range may have a defined name. Typically, the first row of the range contains the headers (or field names), and all later rows in the range contain the records.

The following code adds two new records to a table in Book7.xls. The table in this case is Sheet1.

       'Establish a connection to the data source.
        Dim sConnectionString As String
        sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
            "Data Source=" & sSampleFolder & _
            "Book7.xls;Extended Properties=Excel 8.0;"
        Dim objConn As New System.Data.OleDb.OleDbConnection(sConnectionString)
        objConn.Open()

        'Add two records to the table.
        Dim objCmd As New System.Data.OleDb.OleDbCommand()
        objCmd.Connection = objConn
        objCmd.CommandText = "Insert into [Sheet1$] (FirstName, LastName)" & _
            " values ('Bill', 'Brown')"
        objCmd.ExecuteNonQuery()
        objCmd.CommandText = "Insert into [Sheet1$] (FirstName, LastName)" & _
            " values ('Joe', 'Thomas')"
        objCmd.ExecuteNonQuery()

        'Close the connection.
        objConn.Close()
                

When you add records with ADO.NET as shown, the formatting in the workbook is maintained. Each record that is added to a row borrows the format from the row before it. For example, new fields that are added to column B are formatted with right alignment because cell B1 is right-aligned.

Note that when a record is added to a cell or cells in the worksheet, it overwrites any data that those cells previously contained. In other words, rows in the worksheet are not "pushed down" when new records are added. Keep this in mind when you design the layout of data on your worksheets if you plan to the insert new records by using ADO.NET.

For more information about how to use ADO.NET, click the following article numbers to view the articles in the Microsoft Knowledge Base:

301075 How to connect to a database and run a command by using ADO.NET and Visual Basic .NET


301216 How to populate a DataSet object from a database by using Visual Basic .NET


301248 How to update a database from a DataSet object by using Visual Basic .NET


For more information about how to use the Jet OLE DB provider with Excel data sources, click the following article number to view the article in the Microsoft Knowledge Base:

278973 ExcelADO demonstrates how to use ADO to read and write data in Excel workbooks


257819 How to use ADO with Excel data from Visual Basic or VBA


Transfer XML data (Excel 2002 only)

Excel 2002 can open any XML file that is well-formed. XML files can be opened directly from the Open command on the File menu, or programmatically by using either the Open or OpenXML methods of the Workbooks collection. If you create XML files for use in Excel, you can also create style sheets to format the data.

For more information about how to use XML with Excel 2002, click the following article numbers to view the articles in the Microsoft Knowledge Base:

307021 How to transfer XML data to Microsoft Excel 2002 by using Visual Basic .NET


288215 Microsoft Excel 2002 and XML


Create the complete sample Visual Basic .NET project

  1. Create a new folder to hold the Excel workbooks that the sample will create for you, and then name the folder C:\Exceldata\.
  2. Follow these steps to create a new workbook for the sample to write to:
    1. Start a new workbook in Excel.
    2. On Sheet1 of the new workbook, type FirstName in cell A1 and LastName in cell A2.
    3. Save the workbook as C:\Exceldata\Book7.xls.
  3. Start Visual Studio .NET. On the File menu, click New and then click Project. Under Visual Basic Projects, select Windows Application. By default, Form1 is created.
  4. Add a reference to the Excel object library. To do this, follow these steps:
    1. On the Project menu, click Add Reference.
    2. On the COM tab, locate Microsoft Excel 10.0 Object Library, and then click Select.

      Note If you have not already done so, Microsoft recommends that you download and then install the Microsoft Office XP Primary Interop Assemblies (PIAs). For more information about Office XP PIAs, click the following article number to view the article in the Microsoft Knowledge Base:

      328912 Microsoft Office XP primary interop assemblies (PIAs) are available for download

    3. On the COM tab, locate Microsoft ActiveX Data Objects 2.7 Library, and then click Select.
    4. Click OK in the Add References dialog box to accept your selections. If you receive a prompt to generate wrappers for the libraries that you selected, click Yes.
  5. Add a Combo Box control and a Button control to Form1.
  6. Add the following code to Form1.

        Const sSampleFolder = "C:\ExcelData\"
        Const sNorthwind = "C:\Program Files\Microsoft Office\Office10\Samples\Northwind.mdb"
    
        Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) _
          Handles MyBase.Load
            ComboBox1.DropDownStyle = ComboBoxStyle.DropDownList
            Dim aList As String() = _
                {"Use Automation to Transfer Data Cell by Cell ", _
                 "Use Automation to Transfer an Array of Data to a Range on a Worksheet ", _
                 "Use Automation to Transfer an ADO Recordset to a Worksheet Range ", _
                 "Use Automation to Create a QueryTable on a Worksheet", _
                 "Use the Clipboard", _
                 "Create a Delimited Text File that Excel Can Parse into Rows and Columns", _
                 "Transfer Data to a Worksheet Using ADO.NET "}
            ComboBox1.Items.AddRange(aList)
            ComboBox1.SelectedIndex = 0
            Button1.Text = "Go!"
        End Sub
    
        Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
          Handles Button1.Click
            Select Case ComboBox1.SelectedIndex
                Case 0 : Automation_CellByCell()
                Case 1 : Automation_UseArray()
                Case 2 : Automation_ADORecordset()
                Case 3 : Automation_QueryTable()
                Case 4 : Use_Clipboard()
                Case 5 : Create_TextFile()
                Case 6 : Use_ADONET()
            End Select
            GC.Collect()
        End Sub
    
        Private Function Automation_CellByCell()
            Dim oExcel As Object
            Dim oBook As Object
            Dim oSheet As Object
    
            'Start a new workbook in Excel.
            oExcel = CreateObject("Excel.Application")
            oBook = oExcel.Workbooks.Add
    
            'Add data to cells of the first worksheet in the new workbook.
            oSheet = oBook.Worksheets(1)
            oSheet.Range("A1").Value = "Last Name"
            oSheet.Range("B1").Value = "First Name"
            oSheet.Range("A1:B1").Font.Bold = True
            oSheet.Range("A2").Value = "Doe"
            oSheet.Range("B2").Value = "John"
    
            'Save the workbook and quit Excel.
            oBook.SaveAs(sSampleFolder & "Book1.xls")
            oSheet = Nothing
            oBook = Nothing
            oExcel.Quit()
            oExcel = Nothing
            GC.Collect()
        End Function
    
        Private Function Automation_UseArray()
            Dim oExcel As Object
            Dim oBook As Object
            Dim oSheet As Object
    
            'Start a new workbook in Excel.
            oExcel = CreateObject("Excel.Application")
            oBook = oExcel.Workbooks.Add
    
            'Create an array with 3 columns and 100 rows.
            Dim DataArray(99, 2) As Object
            Dim r As Integer
            For r = 0 To 99
                DataArray(r, 0) = "ORD" & Format(r + 1, "0000")
                DataArray(r, 1) = Rnd() * 1000
                DataArray(r, 2) = DataArray(r, 1) * 0.07
            Next
    
            'Add headers to the worksheet on row 1.
            oSheet = oBook.Worksheets(1)
            oSheet.Range("A1").Value = "Order ID"
            oSheet.Range("B1").Value = "Amount"
            oSheet.Range("C1").Value = "Tax"
    
            'Transfer the array to the worksheet starting at cell A2.
            oSheet.Range("A2").Resize(100, 3).Value = DataArray
    
            'Save the workbook and quit Excel.
            oBook.SaveAs(sSampleFolder & "Book2.xls")
            oSheet = Nothing
            oBook = Nothing
            oExcel.Quit()
            oExcel = Nothing
            GC.Collect()
        End Function
    
        Private Function Automation_ADORecordset()
            'Create a Recordset from all the records in the Orders table.
            Dim sNWind As String
            Dim conn As New ADODB.Connection()
            Dim rs As ADODB.Recordset
            conn.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _
                sNorthwind & ";")
            conn.CursorLocation = ADODB.CursorLocationEnum.adUseClient
            rs = conn.Execute("Orders", , ADODB.CommandTypeEnum.adCmdTable)
    
            'Create a new workbook in Excel.
            Dim oExcel As Object
            Dim oBook As Object
            Dim oSheet As Object
            oExcel = CreateObject("Excel.Application")
            oBook = oExcel.Workbooks.Add
            oSheet = oBook.Worksheets(1)
    
            'Transfer the field names to Row 1 of the worksheet:
            'Note: CopyFromRecordset copies only the data and not the field
            '      names, so you can transfer the fieldnames by traversing the
            '      fields collection.
            Dim n As Int32
            For n = 1 To rs.Fields.Count
                oSheet.Cells(1, n).Value = rs.Fields(n - 1).Name
            Next
    
            'Transfer the data to Excel.
            oSheet.Range("A2").CopyFromRecordset(rs)
    
            'Save the workbook and quit Excel.
            oBook.SaveAs(sSampleFolder & "Book3.xls")
            oSheet = Nothing
            oBook = Nothing
            oExcel.Quit()
            oExcel = Nothing
            GC.Collect()
    
            'Close the connection.
            rs.Close()
            conn.Close()
        End Function
    
        Private Function Automation_QueryTable()
            'Create a new workbook in Excel.
            Dim oExcel As Object
            Dim oBook As Object
            Dim oSheet As Object
            oExcel = CreateObject("Excel.Application")
            oBook = oExcel.Workbooks.Add
            oSheet = oBook.Worksheets(1)
    
            'Create the QueryTable object.
            Dim oQryTable As Object
            oQryTable = oSheet.QueryTables.Add( _
            "OLEDB;Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & _
                sNorthwind & ";", oSheet.Range("A1"), _
                "Select * from Orders")
            oQryTable.RefreshStyle = 2 ' xlInsertEntireRows = 2
            oQryTable.Refresh(False)
    
            'Save the workbook and quit Excel.
            oBook.SaveAs(sSampleFolder & "Book4.xls")
            oQryTable = Nothing
            oSheet = Nothing
            oBook = Nothing
            oExcel.Quit()
    
    
            oExcel = Nothing
    
        End Function
    
        Private Function Use_Clipboard()
            'Copy a string to the clipboard.
            Dim sData As String
            sData = "FirstName" & vbTab & "LastName" & vbTab & "Birthdate" & vbCr _
                & "Bill" & vbTab & "Brown" & vbTab & "2/5/85" & vbCr _
                & "Joe" & vbTab & "Thomas" & vbTab & "1/1/91"
            System.Windows.Forms.Clipboard.SetDataObject(sData)
    
            'Create a new workbook in Excel.
            Dim oExcel As Object
            Dim oBook As Object
            oExcel = CreateObject("Excel.Application")
            oBook = oExcel.Workbooks.Add
    
            'Paste the data.
            oBook.Worksheets(1).Range("A1").Select()
            oBook.Worksheets(1).Paste()
    
            'Save the workbook and quit Excel.
            oBook.SaveAs(sSampleFolder & "Book5.xls")
            oBook = Nothing
            oExcel.Quit()
            oExcel = Nothing
            GC.Collect()
        End Function
    
        Private Function Create_TextFile()
            'Connect to the data source.
            Dim objConn As New System.Data.OleDb.OleDbConnection( _
                "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sNorthwind & ";")
            objConn.Open()
    
            'Run a command to retrieve all records from the Employees table.
            Dim objCmd As New System.Data.OleDb.OleDbCommand( _
                "Select * From Employees", objConn)
            Dim objReader As System.Data.OleDb.OleDbDataReader
            objReader = objCmd.ExecuteReader()
    
            'Read the records in the dataset and write select fields to the 
            'output file.
            FileOpen(1, sSampleFolder & "Book6.txt", OpenMode.Output)
            Dim i As Integer, s As String
            While objReader.Read()
                'Loop through first 6 fields and concatenate
                'each field, separated by a tab, into s variable.
                s = ""
                For i = 0 To 5
                    If Not objReader.IsDBNull(i) Then
                        If i = 0 Then 'field 1 is EmployeeId
                            s = s & objReader.GetInt32(i).ToString
                        ElseIf i = 5 Then 'field 6 is BirthDate
                            s = s & objReader.GetDateTime(i)
                        Else 'field is a text field
                            s = s & objReader.GetString(i)
                        End If
                    End If
                    s = s & Microsoft.VisualBasic.ControlChars.Tab
                Next
                PrintLine(1, s)
            End While
            FileClose(1)
    
            'Close the reader and the connection.
            objReader.Close()
            objConn.Close()
    
            'Create a new instance of Excel.
            Dim oExcel As Object
            oExcel = CreateObject("Excel.Application")
    
            'Open the text file and save it in the Excel workbook format.
            oExcel.Workbooks.OpenText(sSampleFolder & "Book6.txt", _
                , , , -4142, , True) 'xlTextQualifierNone=-4142
    
            oExcel.ActiveWorkbook.SaveAs(sSampleFolder & "Book6.xls", _
                -4143) 'xlWorkbookNormal = -4143
    
            'Quit Excel.
            oExcel.Quit()
            oExcel = Nothing
            GC.Collect()
        End Function
    
        Private Function Use_ADONET()
    
            'Verify that the workbook to write to does exist.
            Dim sFile As String = sSampleFolder & "Book7.xls"
            If Dir(sFile) = "" Then
                MsgBox("Please create the workbook Book7.xls and try again.")
                Exit Function
            End If
    
            'Establish a connection to the data source.
            Dim sConnectionString As String
            sConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;" & _
                "Data Source=" & sSampleFolder & _
                "Book7.xls;Extended Properties=Excel 8.0;"
            Dim objConn As New System.Data.OleDb.OleDbConnection(sConnectionString)
            objConn.Open()
    
            'Add two records to the table named 'MyTable'.
            Dim objCmd As New System.Data.OleDb.OleDbCommand()
            objCmd.Connection = objConn
            objCmd.CommandText = "Insert into [Sheet1$] (FirstName, LastName)" & _
                " values ('Bill', 'Brown')"
            objCmd.ExecuteNonQuery()
            objCmd.CommandText = "Insert into [Sheet1$] (FirstName, LastName)" & _
                " values ('Joe', 'Thomas')"
            objCmd.ExecuteNonQuery()
    
            'Close the connection.
            objConn.Close()
        End Function
                        

    Note If you did not install Office to the default folder (C:\Program Files\Microsoft Office), change the sNorthwind constant in the code sample to match your installation path for Northwind.mdb.

  7. Add the following code to the top of Form1.vb.

    Imports Microsoft.Office.Interop
                        
  8. Press F5 to build and then run the sample.


REFERENCES

For more information, visit the following Microsoft Developer Network (MSDN) Web site:

For more information, click the following article number to view the article in the Microsoft Knowledge Base:

247412 Methods for transferring data to Excel from Visual Basic


Keywords: kbautomation kbhowtomaster KB306022