在网看到了一个Silverlight导出DataGrid里的数据到Excel或xml文件里

//--> DataGrid 扩展方法
public static void Export(this DataGrid dg)
{
    ExportDataGrid(dg);
}
public static void ExportDataGrid(DataGrid dGrid)
{
    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;
	}
        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 object
                    DependencyObject 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();
			}
                        else
			{
                            strValue = 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());
        if (strFormat == "XML")
        {
            //Let us write the headers for the Excel XML
            sw.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();
    }
}
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(",", lstFields.ToArray()));
            break;
    }
}
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;
}