C#3.0入门系列（七）--之OR工具介绍

不得不再次给关注dlinq的朋友道歉了。好久都没有更新blog了。因为工作的变动，还要赶期限，没有时间关注这里了。

先发布一则消息。Orcas Beta1， 这个才是beta1，可以到http://www.microsoft.com/downloads/details.aspx?FamilyID=f10fb5df-e369-4db4-b9a7-845dbf793368&DisplayLang=en 下载。5月1号的版本。最早4月19号就出来过一个，只是没有在意。还有一个http://www.microsoft.com/downloads/details.aspx?FamilyID=36b6609e-6f3d-40f4-8c7d-ad111679d8dc&DisplayLang=en 。 一个是self-extracting 版本的，一个是Virtual PC version的。不知道什么区别。没有装过。

本节舍去原来的计划，而改讲映射工具。在入门三一文中，我们提到了sqlmetal这个工具。http://www.cnblogs.com/126/archive/2006/09/06/492332.html sqlmetal的功能是将数据库的信息抽提出来，生成映射代码。Orcas还有另外一个工具，就是O/R Designer.

先讲sqlmetal. 自上次的版本后，sqlmetal，又增加了一些新的功能。比如，支持SQLCE版本的Sql Server, 支持直接输入connection string， 等等。 这是sqlmetal的帮助信息，是不是比上次多了很多？

< input  file > ]

  Generates code and mapping for the LINQ to SQL component of the .NET framework. SqlMetal can:
  - Generate source code and mapping attributes or a mapping file from a database.
  - Generate an intermediate dbml file for customization from the database.
  - Generate code and mapping attributes or mapping file from a dbml file.

Options:
  /server: < name >              Database server name.
  /database: < name >            Database catalog on server.
  /user: < name >                Login user ID (default: use Windows Authentication).
  /password: < password >        Login password (default: use Windows Authentication).
  /conn: < connection  string >   Database connection string. Cannot be used with /server, /database, /us
er or /password options.
  /timeout: < seconds >          Timeout value to use when SqlMetal accesses the database (default: 0 wh
ich means infinite).

  /views                     Extract database views.
  /functions                 Extract database functions.
  /sprocs                    Extract stored procedures.

  /dbml[:file]               Output as dbml. Cannot be used with /map option.
  /code[:file]               Output as source code. Cannot be used with /dbml option.
  /map[:file]                Generate mapping file, not attributes. Cannot be used with /dbml option
.

  /language: < language >        Language for source code: VB or C# (default: derived from extension on code file name).
  /namespace: < name >           Namespace of generated code (default: no namespace).
  /context: < type >             Name of data context class (default: derived from database name).
  /entitybase: < type >          Base class of entity classes in the generated code (default: entities have no base class).
  /pluralize                 Automatically pluralize or singularize class and member names using English language rules.
  /serialization: < option >     Generate serializable classes: None or Unidirectional (default: None).
  /provider: < type >            Provider type (default: provider is determined at run time).

   < input  file >                May be a SqlExpress mdf file, a SqlCE sdf file, or a dbml intermediate file.

Create code from SqlServer:
  SqlMetal /server:myserver /database:northwind /code:nwind.cs /namespace:nwind

Generate intermediate dbml file from SqlServer:
  SqlMetal /server:myserver /database:northwind /dbml:northwind.dbml /namespace:nwind

Generate code with external mapping from dbml:
  SqlMetal /code:nwind.cs /map:nwind.map northwind.dbml

Generate dbml from a SqlCE sdf file:
  SqlMetal /dbml:northwind.dbml northwind.sdf

Generate dbml from SqlExpress local server:
  SqlMetal /server:."sqlexpress /database:northwind /dbml:northwind.dbml

Generate dbml by using a connection string in the command line:
  SqlMetal /conn:"server='myserver'; database='northwind'" /dbml:northwind.dbml

 
因为sqlmetal已经讲过，不再多讲，大家知道它是个命令行的工具，用来做映射数据库信息的，会使用就可以。再接着讲O/R Designer. 新建任一工程。右击工程，选择add->new item. 如图所示：

弹出item对话框，category中选择data,然后选择Linq to Sql Class， 如图所示：

选择添加。这样，你的工程就多了一个O/R Desiger项目。在菜单View->Sever Explore 打开Sever Explore，添加一个Data Connection, 如图所示：

后，填写数据库服务器，用户名，密码和数据库名。如果，你没有，你可以使用Sql Express 版本。添加之后的效果，如图所示：

打开刚才添加的DataClasses1.dbml 文件，将Sever Explore中的Customer 表或view拖入Designer中来，如图所示：

也可以将Store procedure 和 User define function 拖进来，会在方法面板上形成方法。如图所示：

 

如果，两个表之间有关系，OR Designer可以显示它们的关系，将Order表和 OderDetail表拖入 如图所示：

打开DataClasses1. Designer.cs 文件，你就可以看到OR Designer给你产生的映射代码了。

 System.Data.Linq;
     using  System.Data.Linq.Mapping;
     using  System.Data;
     using  System.Collections.Generic;
     using  System.Reflection;
     using  System.Linq;
     using  System.Linq.Expressions;
     using  System.ComponentModel;
     using  System;
    
    
    [System.Data.Linq.Mapping.DatabaseAttribute(Name = " northwind_may06ctp " )]
     public  partial  class  DataClasses1DataContext : System.Data.Linq.DataContext
     {
        
        private static System.Data.Linq.Mapping.MappingSource mappingSource = new AttributeMappingSource();
        
    Extensibility Method Definitions Extensibility Method Definitions
    partial void OnCreated();
    partial void InsertOrder(Order instance);
    partial void UpdateOrder(Order instance);
    partial void DeleteOrder(Order instance);
    partial void InsertOrder_Detail(Order_Detail instance);
    partial void UpdateOrder_Detail(Order_Detail instance);
    partial void DeleteOrder_Detail(Order_Detail instance);
    #endregion
        
         static  DataClasses1DataContext()
         {
        }
        
         public  DataClasses1DataContext( string  connection) : 
                 base (connection, mappingSource)
         {
            OnCreated();
        }
        
         public  DataClasses1DataContext(System.Data.IDbConnection connection) : 
                 base (connection, mappingSource)
         {
            OnCreated();
        }
        
         public  DataClasses1DataContext( string  connection, System.Data.Linq.Mapping.MappingSource mappingSource) : 
                 base (connection, mappingSource)
         {
            OnCreated();
        }
        
         public  DataClasses1DataContext(System.Data.IDbConnection connection, System.Data.Linq.Mapping.MappingSource mappingSource) : 
                 base (connection, mappingSource)
         {
            OnCreated();
        }
        
         public  DataClasses1DataContext() : 
                 base (global::SqlMetalUtil.Properties.Settings.Default.northwind_may06ctpConnectionString, mappingSource)
         {
            OnCreated();
        }
        
         public  System.Data.Linq.Table < Order >  Orders
         {
            get
            {
                return this.GetTable<Order>();
            }
        }
        
         public  System.Data.Linq.Table < Order_Detail >  Order_Details
         {
            get
            {
                return this.GetTable<Order_Detail>();
            }
        }
        
        [Function(Name = " dbo.CategoriesInsert " )]
         public  int  CategoriesInsert([Parameter(Name = " @CategoryID " , DbType = " int " )] System.Nullable < int >  CategoryID, [Parameter(Name = " @CategoryName " , DbType = " nvarchar " )]  string  CategoryName, [Parameter(Name = " @Description " , DbType = " ntext " )]  string  Description, [Parameter(Name = " @Picture " , DbType = " image " )]  byte [] Picture)
         {
            IExecuteResult result = this.ExecuteMethodCall(this, ((MethodInfo)(MethodInfo.GetCurrentMethod())), CategoryID, CategoryName, Description, Picture);
            return ((int)(result.ReturnValue));
        }
    }
    
    [Table(Name = " dbo.Orders " )]
     public  partial  class  Order : INotifyPropertyChanging, INotifyPropertyChanged
     {
        
        private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);
        
        private int _OrderID;
        
        private string _CustomerID;
        
        private System.Nullable<int> _EmployeeID;
        
        private System.Nullable<System.DateTime> _OrderDate;
        
        private System.Nullable<System.DateTime> _RequiredDate;
        
        private System.Nullable<System.DateTime> _ShippedDate;
        
        private System.Nullable<int> _ShipVia;
        
        private System.Nullable<decimal> _Freight;
        
        private string _ShipName;
        
        private string _ShipAddress;
        
        private string _ShipCity;
        
        private string _ShipRegion;
        
        private string _ShipPostalCode;
        
        private string _ShipCountry;
        
        private EntitySet<Order_Detail> _Order_Details;
        
    Extensibility Method Definitions Extensibility Method Definitions
    partial void OnLoaded();
    partial void OnValidate();
    partial void OnCreated();
    partial void OnOrderIDChanging(int value);
    partial void OnOrderIDChanged();
    partial void OnCustomerIDChanging(string value);
    partial void OnCustomerIDChanged();
    partial void OnEmployeeIDChanging(System.Nullable<int> value);
    partial void OnEmployeeIDChanged();
    partial void OnOrderDateChanging(System.Nullable<System.DateTime> value);
    partial void OnOrderDateChanged();
    partial void OnRequiredDateChanging(System.Nullable<System.DateTime> value);
    partial void OnRequiredDateChanged();
    partial void OnShippedDateChanging(System.Nullable<System.DateTime> value);
    partial void OnShippedDateChanged();
    partial void OnShipViaChanging(System.Nullable<int> value);
    partial void OnShipViaChanged();
    partial void OnFreightChanging(System.Nullable<decimal> value);
    partial void OnFreightChanged();
    partial void OnShipNameChanging(string value);
    partial void OnShipNameChanged();
    partial void OnShipAddressChanging(string value);
    partial void OnShipAddressChanged();
    partial void OnShipCityChanging(string value);
    partial void OnShipCityChanged();
    partial void OnShipRegionChanging(string value);
    partial void OnShipRegionChanged();
    partial void OnShipPostalCodeChanging(string value);
    partial void OnShipPostalCodeChanged();
    partial void OnShipCountryChanging(string value);
    partial void OnShipCountryChanged();
    #endregion
        
         public  Order()
         {
            OnCreated();
            this._Order_Details = new EntitySet<Order_Detail>(new Action<Order_Detail>(this.attach_Order_Details), new Action<Order_Detail>(this.detach_Order_Details));
        }
        
        [Column(Storage = " _OrderID " , AutoSync = AutoSync.OnInsert, DbType = " Int NOT NULL IDENTITY " , IsPrimaryKey = true , IsDbGenerated = true )]
         public  int  OrderID
         {
            get
            {
                return this._OrderID;
            }
            set
            {
                if ((this._OrderID != value))
                {
                    this.OnOrderIDChanging(value);
                    this.SendPropertyChanging();
                    this._OrderID = value;
                    this.SendPropertyChanged("OrderID");
                    this.OnOrderIDChanged();
                }
            }
        }
        
        [Column(Storage = " _CustomerID " , DbType = " NChar(5) " )]
         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 = " _EmployeeID " , DbType = " Int " )]
         public  System.Nullable < int >  EmployeeID
         {
            get
            {
                return this._EmployeeID;
            }
            set
            {
                if ((this._EmployeeID != value))
                {
                    this.OnEmployeeIDChanging(value);
                    this.SendPropertyChanging();
                    this._EmployeeID = value;
                    this.SendPropertyChanged("EmployeeID");
                    this.OnEmployeeIDChanged();
                }
            }
        }
        
        [Column(Storage = " _OrderDate " , DbType = " DateTime " )]
         public  System.Nullable < System.DateTime >  OrderDate
         {
            get
            {
                return this._OrderDate;
            }
            set
            {
                if ((this._OrderDate != value))
                {
                    this.OnOrderDateChanging(value);
                    this.SendPropertyChanging();
                    this._OrderDate = value;
                    this.SendPropertyChanged("OrderDate");
                    this.OnOrderDateChanged();
                }
            }
        }
        
        [Column(Storage = " _RequiredDate " , DbType = " DateTime " )]
         public  System.Nullable < System.DateTime >  RequiredDate
         {
            get
            {
                return this._RequiredDate;
            }
            set
            {
                if ((this._RequiredDate != value))
                {
                    this.OnRequiredDateChanging(value);
                    this.SendPropertyChanging();
                    this._RequiredDate = value;
                    this.SendPropertyChanged("RequiredDate");
                    this.OnRequiredDateChanged();
                }
            }
        }
        
        [Column(Storage = " _ShippedDate " , DbType = " DateTime " )]
         public  System.Nullable < System.DateTime >  ShippedDate
         {
            get
            {
                return this._ShippedDate;
            }
            set
            {
                if ((this._ShippedDate != value))
                {
                    this.OnShippedDateChanging(value);
                    this.SendPropertyChanging();
                    this._ShippedDate = value;
                    this.SendPropertyChanged("ShippedDate");
                    this.OnShippedDateChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipVia " , DbType = " Int " )]
         public  System.Nullable < int >  ShipVia
         {
            get
            {
                return this._ShipVia;
            }
            set
            {
                if ((this._ShipVia != value))
                {
                    this.OnShipViaChanging(value);
                    this.SendPropertyChanging();
                    this._ShipVia = value;
                    this.SendPropertyChanged("ShipVia");
                    this.OnShipViaChanged();
                }
            }
        }
        
        [Column(Storage = " _Freight " , DbType = " Money " )]
         public  System.Nullable < decimal >  Freight
         {
            get
            {
                return this._Freight;
            }
            set
            {
                if ((this._Freight != value))
                {
                    this.OnFreightChanging(value);
                    this.SendPropertyChanging();
                    this._Freight = value;
                    this.SendPropertyChanged("Freight");
                    this.OnFreightChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipName " , DbType = " NVarChar(40) " )]
         public  string  ShipName
         {
            get
            {
                return this._ShipName;
            }
            set
            {
                if ((this._ShipName != value))
                {
                    this.OnShipNameChanging(value);
                    this.SendPropertyChanging();
                    this._ShipName = value;
                    this.SendPropertyChanged("ShipName");
                    this.OnShipNameChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipAddress " , DbType = " NVarChar(60) " )]
         public  string  ShipAddress
         {
            get
            {
                return this._ShipAddress;
            }
            set
            {
                if ((this._ShipAddress != value))
                {
                    this.OnShipAddressChanging(value);
                    this.SendPropertyChanging();
                    this._ShipAddress = value;
                    this.SendPropertyChanged("ShipAddress");
                    this.OnShipAddressChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipCity " , DbType = " NVarChar(15) " )]
         public  string  ShipCity
         {
            get
            {
                return this._ShipCity;
            }
            set
            {
                if ((this._ShipCity != value))
                {
                    this.OnShipCityChanging(value);
                    this.SendPropertyChanging();
                    this._ShipCity = value;
                    this.SendPropertyChanged("ShipCity");
                    this.OnShipCityChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipRegion " , DbType = " NVarChar(15) " )]
         public  string  ShipRegion
         {
            get
            {
                return this._ShipRegion;
            }
            set
            {
                if ((this._ShipRegion != value))
                {
                    this.OnShipRegionChanging(value);
                    this.SendPropertyChanging();
                    this._ShipRegion = value;
                    this.SendPropertyChanged("ShipRegion");
                    this.OnShipRegionChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipPostalCode " , DbType = " NVarChar(10) " )]
         public  string  ShipPostalCode
         {
            get
            {
                return this._ShipPostalCode;
            }
            set
            {
                if ((this._ShipPostalCode != value))
                {
                    this.OnShipPostalCodeChanging(value);
                    this.SendPropertyChanging();
                    this._ShipPostalCode = value;
                    this.SendPropertyChanged("ShipPostalCode");
                    this.OnShipPostalCodeChanged();
                }
            }
        }
        
        [Column(Storage = " _ShipCountry " , DbType = " NVarChar(15) " )]
         public  string  ShipCountry
         {
            get
            {
                return this._ShipCountry;
            }
            set
            {
                if ((this._ShipCountry != value))
                {
                    this.OnShipCountryChanging(value);
                    this.SendPropertyChanging();
                    this._ShipCountry = value;
                    this.SendPropertyChanged("ShipCountry");
                    this.OnShipCountryChanged();
                }
            }
        }
        
        [Association(Name = " Order_Order_Detail " , Storage = " _Order_Details " , OtherKey = " OrderID " )]
         public  EntitySet < Order_Detail >  Order_Details
         {
            get
            {
                return this._Order_Details;
            }
            set
            {
                this._Order_Details.Assign(value);
            }
        }
        
         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));
            }
        }
        
         private  void  attach_Order_Details(Order_Detail entity)
         {
            this.SendPropertyChanging();
            entity.Order = this;
            this.SendPropertyChanged("Order_Details");
        }
        
         private  void  detach_Order_Details(Order_Detail entity)
         {
            this.SendPropertyChanging();
            entity.Order = null;
            this.SendPropertyChanged("Order_Details");
        }
    }
    
    [Table(Name = " dbo.[Order Details] " )]
     public  partial  class  Order_Detail : INotifyPropertyChanging, INotifyPropertyChanged
     {
        
        private static PropertyChangingEventArgs emptyChangingEventArgs = new PropertyChangingEventArgs(String.Empty);
        
        private int _OrderID;
        
        private int _ProductID;
        
        private decimal _UnitPrice;
        
        private short _Quantity;
        
        private float _Discount;
        
        private EntityRef<Order> _Order;
        
    Extensibility Method Definitions Extensibility Method Definitions
    partial void OnLoaded();
    partial void OnValidate();
    partial void OnCreated();
    partial void OnOrderIDChanging(int value);
    partial void OnOrderIDChanged();
    partial void OnProductIDChanging(int value);
    partial void OnProductIDChanged();
    partial void OnUnitPriceChanging(decimal value);
    partial void OnUnitPriceChanged();
    partial void OnQuantityChanging(short value);
    partial void OnQuantityChanged();
    partial void OnDiscountChanging(float value);
    partial void OnDiscountChanged();
    #endregion
        
         public  Order_Detail()
         {
            OnCreated();
            this._Order = default(EntityRef<Order>);
        }
        
        [Column(Storage = " _OrderID " , DbType = " Int NOT NULL " , IsPrimaryKey = true )]
         public  int  OrderID
         {
            get
            {
                return this._OrderID;
            }
            set
            {
                if ((this._OrderID != value))
                {
                    if (this._Order.HasLoadedOrAssignedValue)
                    {
                        throw new System.Data.Linq.ForeignKeyReferenceAlreadyHasValueException();
                    }
                    this.OnOrderIDChanging(value);
                    this.SendPropertyChanging();
                    this._OrderID = value;
                    this.SendPropertyChanged("OrderID");
                    this.OnOrderIDChanged();
                }
            }
        }
        
        [Column(Storage = " _ProductID " , DbType = " Int NOT NULL " , IsPrimaryKey = true )]
         public  int  ProductID
         {
            get
            {
                return this._ProductID;
            }
            set
            {
                if ((this._ProductID != value))
                {
                    this.OnProductIDChanging(value);
                    this.SendPropertyChanging();
                    this._ProductID = value;
                    this.SendPropertyChanged("ProductID");
                    this.OnProductIDChanged();
                }
            }
        }
        
        [Column(Storage = " _UnitPrice " , DbType = " Money NOT NULL " )]
         public  decimal  UnitPrice
         {
            get
            {
                return this._UnitPrice;
            }
            set
            {
                if ((this._UnitPrice != value))
                {
                    this.OnUnitPriceChanging(value);
                    this.SendPropertyChanging();
                    this._UnitPrice = value;
                    this.SendPropertyChanged("UnitPrice");
                    this.OnUnitPriceChanged();
                }
            }
        }
        
        [Column(Storage = " _Quantity " , DbType = " SmallInt NOT NULL " )]
         public  short  Quantity
         {
            get
            {
                return this._Quantity;
            }
            set
            {
                if ((this._Quantity != value))
                {
                    this.OnQuantityChanging(value);
                    this.SendPropertyChanging();
                    this._Quantity = value;
                    this.SendPropertyChanged("Quantity");
                    this.OnQuantityChanged();
                }
            }
        }
        
        [Column(Storage = " _Discount " , DbType = " Real NOT NULL " )]
         public  float  Discount
         {
            get
            {
                return this._Discount;
            }
            set
            {
                if ((this._Discount != value))
                {
                    this.OnDiscountChanging(value);
                    this.SendPropertyChanging();
                    this._Discount = value;
                    this.SendPropertyChanged("Discount");
                    this.OnDiscountChanged();
                }
            }
        }
        
        [Association(Name = " Order_Order_Detail " , Storage = " _Order " , ThisKey = " OrderID " , IsForeignKey = true )]
         public  Order Order
         {
            get
            {
                return this._Order.Entity;
            }
            set
            {
                Order previousValue = this._Order.Entity;
                if (((previousValue != value) 
                            || (this._Order.HasLoadedOrAssignedValue == false)))
                {
                    this.SendPropertyChanging();
                    if ((previousValue != null))
                    {
                        this._Order.Entity = null;
                        previousValue.Order_Details.Remove(this);
                    }
                    this._Order.Entity = value;
                    if ((value != null))
                    {
                        value.Order_Details.Add(this);
                        this._OrderID = value.OrderID;
                    }
                    else
                    {
                        this._OrderID = default(int);
                    }
                    this.SendPropertyChanged("Order");
                }
            }
        }
        
         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));
            }
        }
    }

本节介绍了O/R Designer的基本用法，下节讲一些比较高级的用法。O/R Designer相对与sqlmetal的好处就可以设计类的继承关系（下节再讲），而sqlmetal 相对于O/R Designer是可以一次性抽提所有表的信息，快速便捷。而且sqlmetal支持一些O/R Designer无法支持的信息提取。