没有Interop的Excel导出

我试图完成从VB.NET（Windows窗体）应用程序导出到Excel。

不幸的是，我不能使用Office Interops，因为应用程序应该可以在每台机器上工作 – 即使没有安装Excel。

我在网上find了下面的例子：

Public Sub ExportDatasetToExcel(ByVal ds As DataSet, Optional ByVal strHeader As String = "Save As") 'Proudly copied from: 'http://www.daniweb.com/software-development/vbnet/threads/368400/write-into-excel-using-oledb-connection#post1583200 Dim fileSave As New SaveFileDialog() fileSave.Filter = "Excel 97-2003 Workbook (*.xls)|*.xls" fileSave.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Desktop) fileSave.Title = strHeader fileSave.ShowDialog() Dim xlsFilePath As String = fileSave.FileName If xlsFilePath = "" Then Exit Sub End If System.IO.File.Copy(storagePath & "\" & "empty.xls", xlsFilePath) Cursor.Current = Cursors.WaitCursor Dim conn As New OleDb.OleDbConnection(String.Format("provider=Microsoft.Jet.OLEDB.4.0; Data Source='{0}';" & "Extended Properties='Excel 8.0;HDR=YES;'", xlsFilePath)) conn.Open() Dim strTableQ(ds.Tables.Count) As String Dim i As Integer = 0 'making table query For i = 0 To ds.Tables.Count - 1 strTableQ(i) = "CREATE TABLE [" & ds.Tables(i).TableName & "](" Dim j As Integer = 0 For j = 0 To ds.Tables(i).Columns.Count - 1 Dim dCol As DataColumn dCol = ds.Tables(i).Columns(j) strTableQ(i) &= " [" & dCol.ColumnName & "] varchar(255) , " Next strTableQ(i) = strTableQ(i).Substring(0, strTableQ(i).Length - 2) strTableQ(i) &= ")" Dim cmd As New OleDb.OleDbCommand(strTableQ(i), conn) cmd.ExecuteNonQuery() Next 'making insert query Dim strInsertQ(ds.Tables.Count - 1) As String For i = 0 To ds.Tables.Count - 1 strInsertQ(i) = "Insert Into " & ds.Tables(i).TableName & " Values (" For k As Integer = 0 To ds.Tables(i).Columns.Count - 1 strInsertQ(i) &= "@" & ds.Tables(i).Columns(k).ColumnName & " , " Next strInsertQ(i) = strInsertQ(i).Substring(0, strInsertQ(i).Length - 2) strInsertQ(i) &= ")" Next 'Now inserting data For i = 0 To ds.Tables.Count - 1 For j As Integer = 0 To ds.Tables(i).Rows.Count - 1 Dim cmd As New OleDb.OleDbCommand(strInsertQ(i), conn) For k As Integer = 0 To ds.Tables(i).Columns.Count - 1 cmd.Parameters.AddWithValue("@" & ds.Tables(i).Columns(k).ColumnName.ToString(), ds.Tables(i).Rows(j)(k).ToString()) Next cmd.ExecuteNonQuery() cmd.Parameters.Clear() Next Next conn.Close() conn.Dispose() Cursor.Current = Cursors.Default End Sub 

此代码工作并将我的数据集导出到.xls文件。

问题：我的程序运行时无法打开这个文件。 看来我的程序还在处理这个文件。 每当我使用Sysinternals Process Explorer时，我都可以看到它。 如果我closures了我的程序，我可以打开这个文件没有任何问题。

我想我必须销毁一些对象或者closures文件。 请任何人都可以帮助一个noob来完成它？

Answer 1

我不知道这是否是问题，可以。 您不要configurationOleDbCommand对象。 它有可能保持对文件的引用。 尝试这个：

 Public Sub ExportDatasetToExcel(ByVal ds As DataSet, Optional ByVal strHeader As String = "Save As") 'Proudly copied from: 'http://www.daniweb.com/software-development/vbnet/threads/368400/write-into-excel-using-oledb-connection#post1583200 Using fileSave As New SaveFileDialog() fileSave.Filter = "Excel 97-2003 Workbook (*.xls)|*.xls" fileSave.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.Desktop) fileSave.Title = strHeader If fileSave.ShowDialog() = Windows.Forms.DialogResult.OK Then Dim xlsFilePath As String = fileSave.FileName If xlsFilePath = "" Then Exit Sub System.IO.File.Copy(storagePath & "\" & "empty.xls", xlsFilePath) Cursor.Current = Cursors.WaitCursor Using conn As New OleDb.OleDbConnection(String.Format("provider=Microsoft.Jet.OLEDB.4.0; Data Source='{0}';" & "Extended Properties='Excel 8.0;HDR=YES;'", xlsFilePath)) conn.Open() Dim strTableQ(ds.Tables.Count) As String Dim i As Integer = 0 'making table query For i = 0 To ds.Tables.Count - 1 strTableQ(i) = "CREATE TABLE [" & ds.Tables(i).TableName & "](" Dim j As Integer = 0 For j = 0 To ds.Tables(i).Columns.Count - 1 Dim dCol As DataColumn dCol = ds.Tables(i).Columns(j) strTableQ(i) &= " [" & dCol.ColumnName & "] varchar(255) , " Next strTableQ(i) = strTableQ(i).Substring(0, strTableQ(i).Length - 2) strTableQ(i) &= ")" Using cmd As New OleDb.OleDbCommand(strTableQ(i), conn) cmd.ExecuteNonQuery() End Using Next 'making insert query Dim strInsertQ(ds.Tables.Count - 1) As String For i = 0 To ds.Tables.Count - 1 strInsertQ(i) = "Insert Into " & ds.Tables(i).TableName & " Values (" For k As Integer = 0 To ds.Tables(i).Columns.Count - 1 strInsertQ(i) &= "@" & ds.Tables(i).Columns(k).ColumnName & " , " Next strInsertQ(i) = strInsertQ(i).Substring(0, strInsertQ(i).Length - 2) strInsertQ(i) &= ")" Next 'Now inserting data For i = 0 To ds.Tables.Count - 1 For j As Integer = 0 To ds.Tables(i).Rows.Count - 1 Using cmd As New OleDb.OleDbCommand(strInsertQ(i), conn) For k As Integer = 0 To ds.Tables(i).Columns.Count - 1 cmd.Parameters.AddWithValue("@" & ds.Tables(i).Columns(k).ColumnName.ToString(), ds.Tables(i).Rows(j)(k).ToString()) Next cmd.ExecuteNonQuery() cmd.Parameters.Clear() End Using Next Next conn.Close() Cursor.Current = Cursors.Default End Using End If End Using End Sub 

还要注意，您使用ShowDialog()方法显示的form也必须放置。