存取类实例的参数最佳的方法当然是串行化技术,串行化支持两种方式:二进制方式,可以高保真的保存类示例,另一种是XML方式,它仅保存公共数据。很可惜.net 2.0的精简框架集仅支持XML方式。
我这里做了一个示例,实现的功能是在PC机上可以画很多图形,用串行化方式保存相关信息,把相关信息下载到wince中,由wince中的c#程序读取串行化信息,并把相关类的实例信息还原出来。
这里面有个关键,图形类有可能有多个(示例为2个),而目前我查相关资料,都是一个类的串行化存取,并且如果你存两个以上的类,用XML是可以存取成功的,但是读取的时候它会告诉你失败。所以这里引入了ArrayList类的相关概念。
也就是说,我定义了一个类,类中的一个属性为ArrayList类的实例,这样用ArrayList实例我可以存储很多的类信息。
同样,不作任何处理用一般方法存储是成功的,但是在读取时,你发现ArrayList实例中的数据,都是object类型,原类型信息丢失!
这怎么办?继续查资料,发现有两种方法可以解决这个问题。
1、 [XmlElement(Type = typeof(YFRect)), XmlElement(Type = typeof(YFCircle))]
public ArrayList gData = new ArrayList(); //图元数据
在类中添加XmlElement声明,把ArrayList 类实例中有可能添加的类都标示出。
2、在存取数据时,用代码告诉XML串行化相关类的类型
Type[] gt = new Type[2]; //图元类型数组
gt[0] = typeof(YFRect);
gt[1] = typeof(YFCircle);
Stream sf = new FileStream(strXmlFile, FileMode.Open, FileAccess.Read, FileShare.None);
XmlSerializer xmls = new XmlSerializer(typeof(YFGraphicsData), gt);
XmlData = (YFGraphicsData)xmls.Deserialize(sf);
sf.Close();
这是运行后的结果:
相关代码:clsGraphics.cs (图元类)
using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
using System.Drawing;
using System.Xml.Serialization;
using System.IO;
using System.Xml;
namespace YFXMLSaveLoad
{
//图元数据类
public class YFGraphicsData
{
//[XmlElement(Type = typeof(YFRect)), XmlElement(Type = typeof(YFCircle))]
//当代码传入类型数组时,则不需要上面的声明
public string strName = "测试";
public string strVer = "V1.0.0";
public ArrayList gData = new ArrayList(); //图元数据
}
//串行化操作类
public class YFXMLSerialize
{
//串行化
public void XMLSerializer(YFGraphicsData XmlData,string strXmlFile)
{
Type[] gt = new Type[2]; //图元类型数组
gt[0] = typeof(YFRect);
gt[1] = typeof(YFCircle);
Stream sf = new FileStream(strXmlFile, FileMode.Create, FileAccess.Write, FileShare.None);
XmlSerializer xmls = new XmlSerializer(typeof(YFGraphicsData), gt);
xmls.Serialize(sf, XmlData);
sf.Close();
}
//反串行化
public void XMLDeserialize(out YFGraphicsData XmlData, string strXmlFile)
{
Type[] gt = new Type[2]; //图元类型数组
gt[0] = typeof(YFRect);
gt[1] = typeof(YFCircle);
Stream sf = new FileStream(strXmlFile, FileMode.Open, FileAccess.Read, FileShare.None);
XmlSerializer xmls = new XmlSerializer(typeof(YFGraphicsData), gt);
XmlData = (YFGraphicsData)xmls.Deserialize(sf);
sf.Close();
}
}
//------------------------------------------------
public class YFGraphicsBase
{
public int width = 1;
//Color类不支持XML串行化
public int color = 0;
public virtual void Draw(Graphics e) { }
}
public class YFRect : YFGraphicsBase
{
public Rectangle xy;
public override void Draw(Graphics e)
{
e.DrawRectangle(new Pen(Color.FromArgb(color), width), xy);
}
}
public class YFCircle : YFGraphicsBase
{
public Rectangle xy;
public override void Draw(Graphics e)
{
e.DrawEllipse(new Pen(Color.FromArgb(color), width), xy);
}
}
}
Form1.cs 窗体代码
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Collections;
using System.Xml.Serialization;
using System.IO;
using System.Reflection;
using System.Runtime.InteropServices;
namespace YFXMLSaveLoad
{
public partial class Form1 : Form
{
YFGraphicsData XmlData = new YFGraphicsData(); //图元数据
YFXMLSerialize XmlWork = new YFXMLSerialize(); //XML串行化方法
public Form1()
{
InitializeComponent();
panel1.Refresh();
}
//自绘
private void button4_Click(object sender, EventArgs e)
{
YFRect yfr001=new YFRect();
YFRect yfr002 = new YFRect();
YFCircle yfc001 = new YFCircle();
yfr001.color = Color.Blue.ToArgb();
yfr001.xy.X = 10;
yfr001.xy.Y = 10;
yfr001.xy.Width = 50;
yfr001.xy.Height = 50;
yfr002.color = Color.FromArgb(0, 0, 0).ToArgb();
yfr002.width = 2;
yfr002.xy.X = 30;
yfr002.xy.Y = 50;
yfr002.xy.Width = 100;
yfr002.xy.Height = 80;
yfc001.color = Color.Red.ToArgb();
yfc001.xy.X = 20;
yfc001.xy.Y = 20;
yfc001.xy.Width = 80;
yfc001.xy.Height = 90;
XmlData.gData.Clear();
XmlData.gData.Add(yfr001);
XmlData.gData.Add(yfc001);
XmlData.gData.Add(yfr002);
panel1.Refresh();
}
//绘图
private void panel1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.Clear(Color.PapayaWhip);
foreach (YFGraphicsBase dw in XmlData.gData)
{
dw.Draw(e.Graphics);
}
textBox1.Text = XmlData.gData.Count.ToString();
}
//清图元
private void button3_Click(object sender, EventArgs e)
{
XmlData.gData.Clear();
panel1.Refresh();
}
//保存图元
private void button2_Click(object sender, EventArgs e)
{
//图元串行化
XmlWork.XMLSerializer(XmlData,"TuData.xml");
//------
MessageBox.Show("OK");
}
//调入图元
private void button1_Click(object sender, EventArgs e)
{
//图元反串行化
XmlWork.XMLDeserialize(out XmlData, "TuData.xml");
//------
panel1.Refresh();
}
}
}
//-----------------------------------