// 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","http://www.deltabis.com/Contact");//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());
   }

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