DataGridView如何快速導出Excel

從DataGridView或DataTable導出Excel文件，爲了按照數據類型設置單元格格式，導出Excel時速度都比較慢，一直找不到好的辦法。

最後從外文網站上找到解決辦法，使用ws.get_Range(excelRange, Type.Missing).Value2方法批量設置單元格的值。詳細代碼以下：

    public void DataToExcelFast(DataGridView dgv, string fName)  
    {  
        try  
        {  
            Excel.Application excel = new Excel.Application();  
            Excel.Workbook wb = excel.Workbooks.Add(true);  
            Excel.Worksheet ws = (Excel.Worksheet)wb.ActiveSheet;  
            ws.Name = fName;  
            string sFile = string.Empty;  
            SaveFileDialog dialog = new SaveFileDialog();  
            dialog.Title = "Save export file";  
            dialog.Filter = "EXECL File(*.xlsx) |.xlsx";  
            dialog.FileName = fName;  
            dialog.FilterIndex = 1;  
            if (dialog.ShowDialog() == DialogResult.OK)  
            {  
                string FileName = dialog.FileName;  
                if (File.Exists(FileName))  
                    File.Delete(FileName);  
                sFile = FileName;  
                excel.Visible = false;  
                excel.DisplayAlerts = false;  
                excel.Calculation = Excel.XlCalculation.xlCalculationManual;  
                ArrayList cols = new ArrayList();  
                #region 列標題，並根據列的數據類型設置Excel列的格式  
                int visibleColumnCount = 0;  
                foreach (DataGridViewColumn col in dgv.Columns)  
                {  
                    if (col.Visible)  
                    {  
                        visibleColumnCount++;  
                        ws.Cells[1, visibleColumnCount].Value2 = col.HeaderText.ToString();  
                        ws.Cells[1, visibleColumnCount].Font.Bold = true;  
                        cols.Add(col.Name);  
                        if (col.ValueType != null)  
                        {  
                            if (col.ValueType.Name.Equals("DateTime"))  
                            {  
                                ws.Columns[visibleColumnCount].NumberFormatLocal = @"yyyy-mm-dd HH:mm";  
                                ws.Columns[visibleColumnCount].Font.Color   
                                    = System.Drawing.ColorTranslator.ToOle(Color.Blue);  
                            }  
                            else if (col.ValueType.Name.Equals("Decimal")   
                                || col.ValueType.Name.Equals("Double"))  
                            {  
                                ws.Columns[visibleColumnCount].NumberFormat = "0.00";  
                            }  
                            else if (col.ValueType.Name.Equals("Int32"))  
                            {  
                                ws.Columns[visibleColumnCount].NumberFormat = "0";  
                            }  
                            else  
                            {  
                                ws.Columns[visibleColumnCount].NumberFormatLocal = @"@";  
                            }  
                        }  
                        else  
                            ws.Columns[visibleColumnCount].NumberFormatLocal = @"@";  
                    }  
                }  
                #endregion  
                #region 寫入行  
                // Copy each DataTable  
                // Copy the DataTable to an object array  
                object[,] rawData = new object[dgv.Rows.Count, cols.Count];  
                // Copy the column names to the first row of the object array  
                for (int col = 0; col < cols.Count; col++)  
                {  
                    rawData[0, col] = cols[col];  
                }  
                // Copy the values to the object array  
                for (int col = 0; col < cols.Count; col++)  
                {  
                    for (int row = 0; row < dgv.Rows.Count; row++)  
                    {  
                        rawData[row, col] = dgv.Rows[row].Cells[cols[col].ToString()].Value;  
                    }  
                }  
                // Calculate the final column letter  
                string finalColLetter = string.Empty;  
                string colCharset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";  
                int colCharsetLen = colCharset.Length;  
                if (cols.Count > colCharsetLen)  
                {  
                    finalColLetter = colCharset.Substring(  
                        (cols.Count - 1) / colCharsetLen - 1, 1);  
                }  
                finalColLetter += colCharset.Substring(  
                        (cols.Count - 1) % colCharsetLen, 1);  
                // Fast data export to Excel  
                string excelRange = string.Format("A2:{0}{1}",  
                    finalColLetter, dgv.Rows.Count + 1);  
                ws.get_Range(excelRange, Type.Missing).Value2 = rawData;  
                #endregion  
                excel.Calculation = Excel.XlCalculation.xlCalculationAutomatic;  
                // 51表示2007-2010格式的xlsx  
                ws.SaveAs(FileName, 51, Type.Missing, Type.Missing,   
                    Type.Missing, Type.Missing,   
                    Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange,   
                    Type.Missing, Type.Missing, Type.Missing);  
                wb.Close(true, Type.Missing, Type.Missing);  
                excel.Quit();  
                // 安全回收進程  
                System.GC.GetGeneration(excel);  
                if (MessageBox.Show("已經導出Excel,您是否要打開？", "提示",  
                     MessageBoxButtons.YesNo) == DialogResult.Yes)  
                    System.Diagnostics.Process.Start(FileName);  
            }  
        }  
        catch (Exception ex)  
        {  
            MessageBox.Show("導出Excel時遇到錯誤\r\n" + ex.Message,  
            "Error",MessageBoxButtons.OK,MessageBoxIcon.Error);  
        }  
    }