将 .NET DataTable 导出到 Microsoft Excel 并格式化结果

Question

我想通过将我的数据导出到 Excel 来设置行高。我尝试了以下操作，但出现

的调试错误

Unable To Cast object type of 'System.Web.UI.WebControls.DataGridItem' to type 'System.Web.UI.WebControls.GridViewRow'

这是我的语法

public void ExportToExcel(DataTable dataTable)
{
  string filename = "Bamo.xls";
  StringWriter tw = new System.IO.StringWriter();
  HtmlTextWriter hw = new System.Web.UI.HtmlTextWriter(tw);
  DataGrid dgGrid = new DataGrid();
  dgGrid.DataSource = dataTable;
  dgGrid.DataBind();
  int j = 0;
  foreach(GridViewRow gvrow in dgGrid.Items)
  {
    if (j % 2 != 0)
    {
        for (int k = 0; k < gvrow.Cells.Count; k++)
        {
            gvrow.Cells[k].Style.Add("Height", "10");
        }
    }
    j++;
  }
}

Answer 1

以下代码片段演示了 .NET DataTable 导出到 MS Excel 与各种数据类型相关的工作表和格式化技术（用 C# 编码）：

public bool Export2Excel(DataTable dataTable)
{
    object misValue = System.Reflection.Missing.Value;

    Microsoft.Office.Interop.Excel.Application _appExcel = null;
    Microsoft.Office.Interop.Excel.Workbook _excelWorkbook = null;
    Microsoft.Office.Interop.Excel.Worksheet _excelWorksheet = null;
    try
    {

        if (dataTable.Rows.Count <= 0) { throw new ArgumentNullException("Table is Empty"); }

        // excel app object
        _appExcel = new Microsoft.Office.Interop.Excel.Application();

        // excel workbook object added to app
        _excelWorkbook = _appExcel.Workbooks.Add(misValue);
        _excelWorksheet = _appExcel.ActiveWorkbook.ActiveSheet as Microsoft.Office.Interop.Excel.Worksheet;

        // column names row (range obj)
        Microsoft.Office.Interop.Excel.Range _columnsNameRange;
        _columnsNameRange = _excelWorksheet.get_Range("A1", misValue).get_Resize(1, dataTable.Columns.Count);

        // column names array to be assigned to _columnNameRange
        string[] _arrColumnNames = new string[dataTable.Columns.Count];

        // set Excel columns NumberFormat property
        // note; most important for decimal-currency, DateTime
        for (int i = 0; i < dataTable.Columns.Count; i++)
        {
            // array of column names
            _arrColumnNames[i] = dataTable.Columns[i].ColumnName;

            string _strType = dataTable.Columns[i].DataType.FullName.ToString();
            switch (_strType)
            {
                case "System.DateTime":
                {
                    _excelWorksheet.Range["A1"].Offset[misValue, i].EntireColumn.NumberFormat = "MM/DD/YY";
                    break;
                }
                case "System.Decimal":
                {
                    _excelWorksheet.Columns["A"].Offset[misValue, i].EntireColumn.NumberFormat = "$ #,###.00";
                    break;
                }
                case "System.Double":
                {
                    _excelWorksheet.Columns["A"].Offset[misValue, i].EntireColumn.NumberFormat = "#.#";
                    break;
                }
                case "System.Int8":
                case "System.Int16":
                case "System.Int32":
                case "System.Int64":
                {
                    // use general format for int
                    //_excelWorksheet.Columns["A"].Offset[misValue, i].EntireColumn.NumberFormat = "####";
                    break;
                }
                default: break;
            }
        }

        // assign array to column headers range, make 'em bold
        _columnsNameRange.set_Value(misValue, _arrColumnNames);
        _columnsNameRange.Font.Bold = true;

        // populate data content row by row
        for (int Idx = 0; Idx < dataTable.Rows.Count; Idx++)
        {
            _excelWorksheet.Range["A2"].Offset[Idx].Resize[1, dataTable.Columns.Count].Value =
            dataTable.Rows[Idx].ItemArray;
        }

        // Autofit all Columns in the range
        _columnsNameRange.Columns.EntireColumn.AutoFit();

        // quit excel app process
        if (_appExcel != null)
        {
            _appExcel.UserControl = false;
            _appExcel.Quit();
        }
        return true;
    }
    catch {  throw; }
    finally
    {
        _excelWorksheet = null;
        _excelWorkbook = null;
        _appExcel = null;
        misValue = null;
    }
}
#endregion

您可以根据自己的特定目的对其进行自定义。希望这可能有所帮助。

Answer 2

我使用你的代码有一段时间了，但为字符串添加了额外的格式：

    case "System.String":
    {
        // format as text
        _excelWorkSheet.Columns["A"].Offset[misValue, i].EntireColumn.NumberFormat = "@";
        break;
    }

这解决了一个问题（HRESULT 异常：0x800A03EC 错误），当您导出到 excel 并且在任何字符串的开头有一个等号 (=) 时。 Excel 将此识别为调用或公式的开始，因此它会尝试解决可能不存在或无法完成的问题。

将 .NET DataTable 导出到 Microsoft Excel 并格式化结果

Export .NET DataTable to Microsoft Excel and Format Results

.net

c#

asp.net

datatable

excel