#眉標=.Net
#副標=Bussiness Object Designing of Windows Forms(1)
#大標=.NET Framework 2.0與Business Object的撰寫
#作者=文／黃忠成


-----box 程式-----

程式1
using System;
using System.ComponentModel;
using System.Collections.Generic;
using System.Text;

namespace UsingBindingSource
{
    public class MyDataObject
    {
        private string _name;
        private int _age;

        public string Name
        {
            get
            {
                return _name;
            }
            set
            {
                _name = value;
            }
        }

        public int Age
        {
            get
            {
                return _age;
            }
            set
            {              
                _age = value;
            }
        }

        public MyDataObject(string name, int age)
        {
            _name = name;
            _age = age;
        }

        public MyDataObject()
        {
        }
    }
}-----end-----

-----box 程式-----
程式2
private void Form1_Load(object sender, EventArgs e)
{
        bindingSource1.Add(new MyDataObject("code6421",18));
        textBox1.DataBindings.Add(new Binding("Text", bindingSource1, "Name",true));
        textBox2.DataBindings.Add(new Binding("Text", bindingSource1, "Age",true));
}
-----end-----

-----box 程式-----
程式3
public int Age
{
     get
     {
        return _age;
     }
     set
     {
        if (value > 100)
            throw new Exception("the age can't greater 100.");
         _age = value;
     }
}-----end-----


-----box 程式-----
程式4
private void bindingSource1_BindingComplete(object sender, BindingCompleteEventArgs e)
{
     if (e.BindingCompleteContext == BindingCompleteContext.DataSourceUpdate &&
         e.BindingCompleteState == BindingCompleteState.Exception)
            MessageBox.Show(e.Exception.Message);
}-----end-----


-----box 程式-----
程式5
private void toolStripButton2_Click(object sender, EventArgs e)
{
      bindingSource1.CancelEdit();
}-----end-----


-----box 程式-----
程式6
public class MyDataObject3:IEditableObject
{
　　　　............
        private MyDataObject3 _pendingObject = null;
        void IEditableObject.BeginEdit()
        {
            if (_pendingObject == null)
                _pendingObject = new MyDataObject3(_name, _age);
        }

        void IEditableObject.CancelEdit()
        {
            if (_pendingObject != null)
            {
                _name = _pendingObject._name;
                _age = _pendingObject._age;
            }
            _pendingObject = null;
        }

        void IEditableObject.EndEdit()
        {
            _pendingObject = null;
        }
    }
}-----end-----

-----box 程式-----
程式7
private void Form1_Load(object sender, EventArgs e)
{
      BindingList<MyDataObject4> source = new BindingList<MyDataObject4>();
      bindingSource1.DataSource = source;
      textBox1.DataBindings.Add(new Binding("Text", bindingSource1, "Name",true));
      textBox2.DataBindings.Add(new Binding("Text", bindingSource1, "Age",true));
}-----end-----


-----box 程式-----
程式8
public class MyDataObject4 : IEditableObject
{
        ................
        private MyDataObject4 _originalObject = null;

        public string Name
        {
            get .........
            set
            {
                if (_pendingObject != null)
                    ((IEditableObject)this).BeginEdit();
                MarkDirty();
                _name = value;
            }
        }

        public int Age
        {
            get  ............
            set
            {
                if (value > 100)
                    throw new Exception("the age can't greater 100.");
                if (_pendingObject != null)
                    ((IEditableObject)this).BeginEdit();
                MarkDirty();
                _age = value;
            }
        }

        [Browsable(false)]
        public MyDataObject4 OriginalObject
        {
            get
            {
                return _originalObject;
            }
        }

        .............

        private void MarkDirty()
        {
            if (_originalObject == null)
                _originalObject = new MyDataObject4(_name,_age);
        }

        public void AcceptChanges()
        {
            _originalObject = null;
        }

        public void RevertChanges()
        {
            if (_originalObject != null)
            {
                _name = _originalObject._name;
                _age = _originalObject._age;
                _originalObject = null;
            }            
        }
}-----end-----