string xmlFileName=strTempXml;
XmlTextWriter xw=new XmlTextWriter(xmlFileName,Encoding.UTF8);
xw.WriteStartDocument();
xw.WriteStartElement("image");
xw.WriteString(photo);
xw.WriteEndElement();
xw.WriteEndDocument();
xw.Flush();
xw.Close();
//寫入xml成功
//從xml讀入到圖片
XmlTextReader xr=new XmlTextReader(strTempXml);
byte[] buffer = new byte[bufferSize];
int readByte=0;
//Create a file to write the bmp back. jpgNewFile表示新圖片
this.jpgPackFile=this.jpgPackFile.Replace(".jpg",j+".jpg");
FileStream fileNew = new FileStream(this.jpgPackFile, FileMode.Create, FileAccess.ReadWrite, FileShare.ReadWrite);
BinaryWriter bw = new BinaryWriter(fileNew);
xr.MoveToContent();
do
{
readByte=xr.ReadBase64(buffer, 0, bufferSize);
bw.Write(buffer, 0, readByte);
} while(readByte>=bufferSize);
bw.Flush();
bw.Close();
fileNew.Close();
xr.Close();//關閉 !!!!