public void SaveMapToFile(string filename)
{
map.ClearAttachment();
//Create the file.
using (FileStream fs = File.Create(filename))
{
map.ClearArray();//清空数组内容再存储，以节省存储空间
BinaryFormatter formatter = new BinaryFormatter();
formatter.Serialize(fs, map);
fs.Close();
map.RestoreArrayFromList();//从List恢复内容到数组
}
}