LINQ to SQL 用O/R设计器手工建表对象

除了自己建立定制对象外，还可以使用O/R设计器以可视化的方式创建数据对象和关系。

双击DBML文件打开OR设计器，从工具栏拖动一个类进来，改名为Customers并右键->添加属性，设置CustomerID属性为主键，设置源属性为数据库中的dbo.Customers表，注意这里加上了dbo。

结果如下：

这时候可以打开

dbml.layout文件和designer.cs 文件查看结果发现多了下面的内容

[Table(Name="dbo.Customers")]
    public partial class Customers : INotifyPropertyChanging, INotifyPropertyChanged
    {
        
        private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);
        
        private string _CompanyName;
        
        private string _CustomerID;
        
        private string _Country;
        
    #region Extensibility Method Definitions
    partial void OnLoaded();
    partial void OnValidate(System.Data.Linq.ChangeAction action);
    partial void OnCreated();
    partial void OnCompanyNameChanging(string value);
    partial void OnCompanyNameChanged();
    partial void OnCustomerIDChanging(string value);
    partial void OnCustomerIDChanged();
    partial void OnCountryChanging(string value);
    partial void OnCountryChanged();
    #endregion
        
        public Customers()
        {
            OnCreated();
        }
        
        [Column(Storage="_CompanyName", CanBeNull=false)]
        public string CompanyName
        {
            get
            {
                return this._CompanyName;
            }
            set
            {
                if ((this._CompanyName != value))
                {
                    this.OnCompanyNameChanging(value);
                    this.SendPropertyChanging();
                    this._CompanyName = value;
                    this.SendPropertyChanged("CompanyName");
                    this.OnCompanyNameChanged();
                }
            }
        }
        
        [Column(Storage="_CustomerID", CanBeNull=false, IsPrimaryKey=true)]
        public string CustomerID
        {
            get
            {
                return this._CustomerID;
            }
            set
            {
                if ((this._CustomerID != value))
                {
                    this.OnCustomerIDChanging(value);
                    this.SendPropertyChanging();
                    this._CustomerID = value;
                    this.SendPropertyChanged("CustomerID");
                    this.OnCustomerIDChanged();
                }
            }
        }
        
        [Column(Storage="_Country", CanBeNull=false)]
        public string Country
        {
            get
            {
                return this._Country;
            }
            set
            {
                if ((this._Country != value))
                {
                    this.OnCountryChanging(value);
                    this.SendPropertyChanging();
                    this._Country = value;
                    this.SendPropertyChanged("Country");
                    this.OnCountryChanged();
                }
            }
        }
        
        public event PropertyChangingEventHandler PropertyChanging;
        
        public event PropertyChangedEventHandler PropertyChanged;
        
        protected virtual void SendPropertyChanging()
        {
            if ((this.PropertyChanging != null))
            {
                this.PropertyChanging(this, emptyChangingEventArgs);
            }
        }
        
        protected virtual void SendPropertyChanged(String propertyName)
        {
            if ((this.PropertyChanged != null))
            {
                this.PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
            }
        }
    }

dbml.layout文件 是用于帮助OR设计器进行可视化表示的XML

designer.cs文件 是定义了所有数据类的文件