首先新建一个DataGrdiExtensions类，代码为：

 public static class DataGridExtensions{/// <summary>/// 导出dg中数据，成功返回true，失败返回false/// </summary>/// <param name="dg"></param>/// <returns></returns>public static bool Export(this DataGrid dg){return ExportDataGrid(dg);}/// <summary>/// 导出dGrid中数据，成功返回true，失败返回false/// </summary>/// <param name="dGrid"></param>/// <returns></returns>public static bool ExportDataGrid(DataGrid dGrid){bool exportOK = false;#region 导出数据try{SaveFileDialog objSFD = new SaveFileDialog() { DefaultExt = "csv", Filter = "CSV Files (*.csv)|*.csv|Excel XML (*.xml)|*.xml|All files (*.*)|*.*", FilterIndex = 1 };if (objSFD.ShowDialog() == true){string strFormat = objSFD.SafeFileName.Substring(objSFD.SafeFileName.IndexOf('.') + 1).ToUpper();StringBuilder strBuilder = new StringBuilder();if (dGrid.ItemsSource == null) return false;List<string> lstFields = new List<string>();if (dGrid.HeadersVisibility == DataGridHeadersVisibility.Column || dGrid.HeadersVisibility == DataGridHeadersVisibility.All){foreach (DataGridColumn dgcol in dGrid.Columns)lstFields.Add(FormatField(dgcol.Header.ToString(), strFormat));BuildStringOfRow(strBuilder, lstFields, strFormat);}foreach (object data in dGrid.ItemsSource){lstFields.Clear();foreach (DataGridColumn col in dGrid.Columns){string strValue = "";Binding objBinding = null;if (col is DataGridBoundColumn)objBinding = (col as DataGridBoundColumn).Binding;if (col is DataGridTemplateColumn){//This is a template column... let us see the underlying dependency objectDependencyObject objDO = (col as DataGridTemplateColumn).CellTemplate.LoadContent();FrameworkElement oFE = (FrameworkElement)objDO;FieldInfo oFI = oFE.GetType().GetField("TextProperty");if (oFI != null){if (oFI.GetValue(null) != null){if (oFE.GetBindingExpression((DependencyProperty)oFI.GetValue(null)) != null)objBinding = oFE.GetBindingExpression((DependencyProperty)oFI.GetValue(null)).ParentBinding;}}}if (objBinding != null){if (objBinding.Path.Path != ""){PropertyInfo pi = data.GetType().GetProperty(objBinding.Path.Path);if (pi != null) strValue = pi.GetValue(data, null).ToString();}if (objBinding.Converter != null){if (strValue != "")strValue = objBinding.Converter.Convert(strValue, typeof(string), objBinding.ConverterParameter, objBinding.ConverterCulture).ToString();elsestrValue = objBinding.Converter.Convert(data, typeof(string), objBinding.ConverterParameter, objBinding.ConverterCulture).ToString();}}lstFields.Add(FormatField(strValue, strFormat));}BuildStringOfRow(strBuilder, lstFields, strFormat);}StreamWriter sw = new StreamWriter(objSFD.OpenFile(), System.Text.Encoding.Unicode);if (strFormat == "XML"){//Let us write the headers for the Excel XMLsw.WriteLine("<?xml version=\"1.0\" encoding=\"utf-8\"?>");sw.WriteLine("<?mso-application progid=\"Excel.Sheet\"?>");sw.WriteLine("<Workbook xmlns=\"urn:schemas-microsoft-com:office:spreadsheet\">");sw.WriteLine("<DocumentProperties xmlns=\"urn:schemas-microsoft-com:office:office\">");sw.WriteLine("<Author>Arasu Elango</Author>");sw.WriteLine("<Created>" + DateTime.Now.ToLocalTime().ToLongDateString() + "</Created>");sw.WriteLine("<LastSaved>" + DateTime.Now.ToLocalTime().ToLongDateString() + "</LastSaved>");sw.WriteLine("<Company>Atom8 IT Solutions (P) Ltd.,</Company>");sw.WriteLine("<Version>12.00</Version>");sw.WriteLine("</DocumentProperties>");sw.WriteLine("<Worksheet ss:Name=\"Silverlight Export\" xmlns:ss=\"urn:schemas-microsoft-com:office:spreadsheet\">");sw.WriteLine("<Table>");}sw.Write(strBuilder.ToString());if (strFormat == "XML"){sw.WriteLine("</Table>");sw.WriteLine("</Worksheet>");sw.WriteLine("</Workbook>");}sw.Close();exportOK = true;}}catch (Exception ex){exportOK = false;MessageBox.Show("保存失败："+ex.Message);}#endregionreturn exportOK;}/// <summary>/// 设置datagrid中每一行的数据内容/// </summary>/// <param name="strBuilder"></param>/// <param name="lstFields"></param>/// <param name="strFormat"></param>private static void BuildStringOfRow(StringBuilder strBuilder, List<string> lstFields, string strFormat){switch (strFormat){case "XML":strBuilder.AppendLine("<Row>");strBuilder.AppendLine(String.Join("\r\n", lstFields.ToArray()));strBuilder.AppendLine("</Row>");break;case "CSV":strBuilder.AppendLine(String.Join("\t", lstFields.ToArray()));break;}}/// <summary>/// 设置字符串输出格式/// </summary>/// <param name="data"></param>/// <param name="format"></param>/// <returns></returns>private static string FormatField(string data, string format){switch (format){case "XML":return String.Format("<Cell><Data ss:Type=\"String\">{0}</Data></Cell>", data);case "CSV":return String.Format("\"{0}\"", data.Replace("\"", "\"\"\"").Replace("\n", "").Replace("\r", ""));}return data;}}

导出数据时，只需要调用方法：datagrid.Export()即可