xml|二进制try
   {
    int readByte = 0;        //
    int bytesToRead = 100;       //数据缓冲区大小
    string fileName = "../../WriteXml.xml";   //要打开的文件
    //   this.textBox1.Text = string.Empty;           

    // 打开图片文件，利用该图片构造一个文件流
    FileStream fs = new FileStream("../../001.jpg",FileMode.Open);
    // 使用文件流构造一个二进制读取器将基元数据读作二进制值
    BinaryReader br = new BinaryReader(fs);

    XmlTextWriter xmlTxtWt = new XmlTextWriter(fileName,Encoding.UTF8);
    //输出设置 代码缩进
    xmlTxtWt.Formatting = Formatting.Indented;
    //   xmlTxtWt.Indentation = 4;

    //书写声明
    xmlTxtWt.WriteStartDocument();
    xmlTxtWt.WriteStartElement("picture","ContactDetails","定义命名空间
    xmlTxtWt.WriteStartElement("image");            //定义节点
    xmlTxtWt.WriteAttributeString("imageName","002.jpg");        //添加图片属性

    byte[] base64buffer = new byte[bytesToRead];          //开辟缓冲区
    do
    {
     readByte = br.Read(base64buffer,0,bytesToRead);      //将数据读入字节数组
     xmlTxtWt.WriteBase64(base64buffer,0,readByte);       //将数组中二进制值编码为Base64并写出到XML文件

    }while(bytesToRead <= readByte);

    xmlTxtWt.WriteEndElement();
    xmlTxtWt.WriteEndElement();
    xmlTxtWt.WriteEndDocument();

//    xmlTxtWt.Flush();
    xmlTxtWt.Close();

    MessageBox.Show("读写结束！");

    //   this.textBox1.Text = ReadXml(fileName);
   }
   catch(Exception ex)
   {
    MessageBox.Show(ex.ToString());
   }