使用Entity Framework和WCF Ria Services开发SilverLight之1：简单模型

本文目的是通过Silverlight ria service完成一次数据的读取过程，并且在此基础上建立测试项目。

Ria service借助于WCF和ADO.NET Entity Framework构建分布式开发框架。使用它可以快速构建自己的开发模式。

1：基础结构

首先，创建SL APP，如下：

然后，选择创建web：

可以，也可以不勾选enable wcf ria service，如果勾选了，在SL APP中会多几个DLL的引用，其它没有任何差别。如图：

2：创建一个示例数据库

这是一个小而轻型的数据库，在MDSN的课程中有使用到它。如下：

SET ANSI_NULLS ONGOSET QUOTED_IDENTIFIER ONGOUSE [master];GOIF EXISTS (SELECT * FROM sys.databases WHERE name = 'School')DROP DATABASE School;GO-- Create the School database.CREATE DATABASE School;GO-- Specify a simple recovery model -- to keep the log growth to a minimum.ALTER DATABASE School SET RECOVERY SIMPLE;GOUSE School;GO-- Create the Department table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[Department]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[Department]([DepartmentID] [int] NOT NULL,[Name] [nvarchar](50) NOT NULL,[Budget] [money] NOT NULL,[StartDate] [datetime] NOT NULL,[Administrator] [int] NULL, CONSTRAINT [PK_Department] PRIMARY KEY CLUSTERED ([DepartmentID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the Person table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[Person]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[Person]([PersonID] [int] IDENTITY(1,1) NOT NULL,[LastName] [nvarchar](50) NOT NULL,[FirstName] [nvarchar](50) NOT NULL,[HireDate] [datetime] NULL,[EnrollmentDate] [datetime] NULL, CONSTRAINT [PK_School.Student] PRIMARY KEY CLUSTERED ([PersonID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the OnsiteCourse table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[OnsiteCourse]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[OnsiteCourse]([CourseID] [int] NOT NULL,[Location] [nvarchar](50) NOT NULL,[Days] [nvarchar](50) NOT NULL,[Time] [smalldatetime] NOT NULL, CONSTRAINT [PK_OnsiteCourse] PRIMARY KEY CLUSTERED ([CourseID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the OnlineCourse table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[OnlineCourse]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[OnlineCourse]([CourseID] [int] NOT NULL,[URL] [nvarchar](100) NOT NULL, CONSTRAINT [PK_OnlineCourse] PRIMARY KEY CLUSTERED ([CourseID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO--Create the StudentGrade table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[StudentGrade]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[StudentGrade]([EnrollmentID] [int] IDENTITY(1,1) NOT NULL,[CourseID] [int] NOT NULL,[StudentID] [int] NOT NULL,[Grade] [decimal](3, 2) NULL, CONSTRAINT [PK_StudentGrade] PRIMARY KEY CLUSTERED ([EnrollmentID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the CourseInstructor table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[CourseInstructor]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[CourseInstructor]([CourseID] [int] NOT NULL,[PersonID] [int] NOT NULL, CONSTRAINT [PK_CourseInstructor] PRIMARY KEY CLUSTERED ([CourseID] ASC,[PersonID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the Course table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[Course]') AND type in (N'U'))BEGINCREATE TABLE [dbo].[Course]([CourseID] [int] NOT NULL,[Title] [nvarchar](100) NOT NULL,[Credits] [int] NOT NULL,[DepartmentID] [int] NOT NULL, CONSTRAINT [PK_School.Course] PRIMARY KEY CLUSTERED ([CourseID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Create the OfficeAssignment table.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[OfficeAssignment]')AND type in (N'U'))BEGINCREATE TABLE [dbo].[OfficeAssignment]([InstructorID] [int] NOT NULL,[Location] [nvarchar](50) NOT NULL,[Timestamp] [timestamp] NOT NULL, CONSTRAINT [PK_OfficeAssignment] PRIMARY KEY CLUSTERED ([InstructorID] ASC)WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY]) ON [PRIMARY]ENDGO-- Define the relationship between OnsiteCourse and Course.IF NOT EXISTS (SELECT * FROM sys.foreign_keys        WHERE object_id = OBJECT_ID(N'[dbo].[FK_OnsiteCourse_Course]')       AND parent_object_id = OBJECT_ID(N'[dbo].[OnsiteCourse]'))ALTER TABLE [dbo].[OnsiteCourse]  WITH CHECK ADD         CONSTRAINT [FK_OnsiteCourse_Course] FOREIGN KEY([CourseID])REFERENCES [dbo].[Course] ([CourseID])GOALTER TABLE [dbo].[OnsiteCourse] CHECK        CONSTRAINT [FK_OnsiteCourse_Course]GO-- Define the relationship between OnlineCourse and Course.IF NOT EXISTS (SELECT * FROM sys.foreign_keys        WHERE object_id = OBJECT_ID(N'[dbo].[FK_OnlineCourse_Course]')       AND parent_object_id = OBJECT_ID(N'[dbo].[OnlineCourse]'))ALTER TABLE [dbo].[OnlineCourse]  WITH CHECK ADD         CONSTRAINT [FK_OnlineCourse_Course] FOREIGN KEY([CourseID])REFERENCES [dbo].[Course] ([CourseID])GOALTER TABLE [dbo].[OnlineCourse] CHECK        CONSTRAINT [FK_OnlineCourse_Course]GO-- Define the relationship between StudentGrade and Course.IF NOT EXISTS (SELECT * FROM sys.foreign_keys        WHERE object_id = OBJECT_ID(N'[dbo].[FK_StudentGrade_Course]')       AND parent_object_id = OBJECT_ID(N'[dbo].[StudentGrade]'))ALTER TABLE [dbo].[StudentGrade]  WITH CHECK ADD         CONSTRAINT [FK_StudentGrade_Course] FOREIGN KEY([CourseID])REFERENCES [dbo].[Course] ([CourseID])GOALTER TABLE [dbo].[StudentGrade] CHECK        CONSTRAINT [FK_StudentGrade_Course]GO--Define the relationship between StudentGrade and Student.IF NOT EXISTS (SELECT * FROM sys.foreign_keys        WHERE object_id = OBJECT_ID(N'[dbo].[FK_StudentGrade_Student]')       AND parent_object_id = OBJECT_ID(N'[dbo].[StudentGrade]'))ALTER TABLE [dbo].[StudentGrade]  WITH CHECK ADD         CONSTRAINT [FK_StudentGrade_Student] FOREIGN KEY([StudentID])REFERENCES [dbo].[Person] ([PersonID])GOALTER TABLE [dbo].[StudentGrade] CHECK        CONSTRAINT [FK_StudentGrade_Student]GO-- Define the relationship between CourseInstructor and Course.IF NOT EXISTS (SELECT * FROM sys.foreign_keys    WHERE object_id = OBJECT_ID(N'[dbo].[FK_CourseInstructor_Course]')   AND parent_object_id = OBJECT_ID(N'[dbo].[CourseInstructor]'))ALTER TABLE [dbo].[CourseInstructor]  WITH CHECK ADD     CONSTRAINT [FK_CourseInstructor_Course] FOREIGN KEY([CourseID])REFERENCES [dbo].[Course] ([CourseID])GOALTER TABLE [dbo].[CourseInstructor] CHECK    CONSTRAINT [FK_CourseInstructor_Course]GO-- Define the relationship between CourseInstructor and Person.IF NOT EXISTS (SELECT * FROM sys.foreign_keys    WHERE object_id = OBJECT_ID(N'[dbo].[FK_CourseInstructor_Person]')   AND parent_object_id = OBJECT_ID(N'[dbo].[CourseInstructor]'))ALTER TABLE [dbo].[CourseInstructor]  WITH CHECK ADD     CONSTRAINT [FK_CourseInstructor_Person] FOREIGN KEY([PersonID])REFERENCES [dbo].[Person] ([PersonID])GOALTER TABLE [dbo].[CourseInstructor] CHECK    CONSTRAINT [FK_CourseInstructor_Person]GO-- Define the relationship between Course and Department.IF NOT EXISTS (SELECT * FROM sys.foreign_keys        WHERE object_id = OBJECT_ID(N'[dbo].[FK_Course_Department]')       AND parent_object_id = OBJECT_ID(N'[dbo].[Course]'))ALTER TABLE [dbo].[Course]  WITH CHECK ADD         CONSTRAINT [FK_Course_Department] FOREIGN KEY([DepartmentID])REFERENCES [dbo].[Department] ([DepartmentID])GOALTER TABLE [dbo].[Course] CHECK CONSTRAINT [FK_Course_Department]GO--Define the relationship between OfficeAssignment and Person.IF NOT EXISTS (SELECT * FROM sys.foreign_keys    WHERE object_id = OBJECT_ID(N'[dbo].[FK_OfficeAssignment_Person]')   AND parent_object_id = OBJECT_ID(N'[dbo].[OfficeAssignment]'))ALTER TABLE [dbo].[OfficeAssignment]  WITH CHECK ADD     CONSTRAINT [FK_OfficeAssignment_Person] FOREIGN KEY([InstructorID])REFERENCES [dbo].[Person] ([PersonID])GOALTER TABLE [dbo].[OfficeAssignment] CHECK    CONSTRAINT [FK_OfficeAssignment_Person]GO-- Create InsertOfficeAssignment stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[InsertOfficeAssignment]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[InsertOfficeAssignment]@InstructorID int,@Location nvarchar(50)ASINSERT INTO dbo.OfficeAssignment (InstructorID, Location)VALUES (@InstructorID, @Location);IF @@ROWCOUNT > 0BEGINSELECT [Timestamp] FROM OfficeAssignment WHERE InstructorID=@InstructorID;END' ENDGO--Create the UpdateOfficeAssignment stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[UpdateOfficeAssignment]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[UpdateOfficeAssignment]@InstructorID int,@Location nvarchar(50),@OrigTimestamp timestampASUPDATE OfficeAssignment SET Location=@Location WHERE InstructorID=@InstructorID AND [Timestamp]=@OrigTimestamp;IF @@ROWCOUNT > 0BEGINSELECT [Timestamp] FROM OfficeAssignment WHERE InstructorID=@InstructorID;END' ENDGO-- Create the DeleteOfficeAssignment stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[DeleteOfficeAssignment]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[DeleteOfficeAssignment]@InstructorID intASDELETE FROM OfficeAssignmentWHERE InstructorID=@InstructorID;' ENDGO-- Create the DeletePerson stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[DeletePerson]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[DeletePerson]@PersonID intASDELETE FROM Person WHERE PersonID = @PersonID;' ENDGO-- Create the UpdatePerson stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[UpdatePerson]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[UpdatePerson]@PersonID int,@LastName nvarchar(50),@FirstName nvarchar(50),@HireDate datetime,@EnrollmentDate datetimeASUPDATE Person SET LastName=@LastName, FirstName=@FirstName,HireDate=@HireDate,EnrollmentDate=@EnrollmentDateWHERE PersonID=@PersonID;' ENDGO-- Create the InsertPerson stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[InsertPerson]') AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[InsertPerson]@LastName nvarchar(50),@FirstName nvarchar(50),@HireDate datetime,@EnrollmentDate datetimeASINSERT INTO dbo.Person (LastName, FirstName, HireDate, EnrollmentDate)VALUES (@LastName, @FirstName, @HireDate, @EnrollmentDate);SELECT SCOPE_IDENTITY() as NewPersonID;' ENDGO-- Create GetStudentGrades stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects             WHERE object_id = OBJECT_ID(N'[dbo].[GetStudentGrades]')             AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[GetStudentGrades]            @StudentID int            AS            SELECT EnrollmentID, Grade, CourseID, StudentID FROM dbo.StudentGrade            WHERE StudentID = @StudentID' ENDGO-- Create GetDepartmentName stored procedure.IF NOT EXISTS (SELECT * FROM sys.objects             WHERE object_id = OBJECT_ID(N'[dbo].[GetDepartmentName]')             AND type in (N'P', N'PC'))BEGINEXEC dbo.sp_executesql @statement = N'CREATE PROCEDURE [dbo].[GetDepartmentName]      @ID int,      @Name nvarchar(50) OUTPUT      AS      SELECT @Name = Name FROM Department      WHERE DepartmentID = @ID'ENDGO-- Insert data into the Person table.USE SchoolGOSET IDENTITY_INSERT dbo.Person ONGOINSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (1, 'Abercrombie', 'Kim', '1995-03-11', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (2, 'Barzdukas', 'Gytis', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (3, 'Justice', 'Peggy', null, '2001-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (4, 'Fakhouri', 'Fadi', '2002-08-06', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (5, 'Harui', 'Roger', '1998-07-01', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (6, 'Li', 'Yan', null, '2002-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (7, 'Norman', 'Laura', null, '2003-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (8, 'Olivotto', 'Nino', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (9, 'Tang', 'Wayne', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (10, 'Alonso', 'Meredith', null, '2002-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (11, 'Lopez', 'Sophia', null, '2004-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (12, 'Browning', 'Meredith', null, '2000-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (13, 'Anand', 'Arturo', null, '2003-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (14, 'Walker', 'Alexandra', null, '2000-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (15, 'Powell', 'Carson', null, '2004-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (16, 'Jai', 'Damien', null, '2001-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (17, 'Carlson', 'Robyn', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (18, 'Zheng', 'Roger', '2004-02-12', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (19, 'Bryant', 'Carson', null, '2001-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (20, 'Suarez', 'Robyn', null, '2004-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (21, 'Holt', 'Roger', null, '2004-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (22, 'Alexander', 'Carson', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (23, 'Morgan', 'Isaiah', null, '2001-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (24, 'Martin', 'Randall', null, '2005-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (25, 'Kapoor', 'Candace', '2001-01-15', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (26, 'Rogers', 'Cody', null, '2002-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (27, 'Serrano', 'Stacy', '1999-06-01', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (28, 'White', 'Anthony', null, '2001-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (29, 'Griffin', 'Rachel', null, '2004-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (30, 'Shan', 'Alicia', null, '2003-09-01');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (31, 'Stewart', 'Jasmine', '1997-10-12', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (32, 'Xu', 'Kristen', '2001-7-23', null);INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (33, 'Gao', 'Erica', null, '2003-01-30');INSERT INTO dbo.Person (PersonID, LastName, FirstName, HireDate, EnrollmentDate)VALUES (34, 'Van Houten', 'Roger', '2000-12-07', null);GOSET IDENTITY_INSERT dbo.Person OFFGO-- Insert data into the Department table.INSERT INTO dbo.Department (DepartmentID, [Name], Budget, StartDate, Administrator)VALUES (1, 'Engineering', 350000.00, '2007-09-01', 2);INSERT INTO dbo.Department (DepartmentID, [Name], Budget, StartDate, Administrator)VALUES (2, 'English', 120000.00, '2007-09-01', 6);INSERT INTO dbo.Department (DepartmentID, [Name], Budget, StartDate, Administrator)VALUES (4, 'Economics', 200000.00, '2007-09-01', 4);INSERT INTO dbo.Department (DepartmentID, [Name], Budget, StartDate, Administrator)VALUES (7, 'Mathematics', 250000.00, '2007-09-01', 3);GO-- Insert data into the Course table.INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (1050, 'Chemistry', 4, 1);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (1061, 'Physics', 4, 1);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (1045, 'Calculus', 4, 7);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (2030, 'Poetry', 2, 2);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (2021, 'Composition', 3, 2);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (2042, 'Literature', 4, 2);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (4022, 'Microeconomics', 3, 4);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (4041, 'Macroeconomics', 3, 4);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (4061, 'Quantitative', 2, 4);INSERT INTO dbo.Course (CourseID, Title, Credits, DepartmentID)VALUES (3141, 'Trigonometry', 4, 7);GO-- Insert data into the OnlineCourse table.INSERT INTO dbo.OnlineCourse (CourseID, URL)VALUES (2030, 'http://www.fineartschool.net/Poetry');INSERT INTO dbo.OnlineCourse (CourseID, URL)VALUES (2021, 'http://www.fineartschool.net/Composition');INSERT INTO dbo.OnlineCourse (CourseID, URL)VALUES (4041, 'http://www.fineartschool.net/Macroeconomics');INSERT INTO dbo.OnlineCourse (CourseID, URL)VALUES (3141, 'http://www.fineartschool.net/Trigonometry');--Insert data into OnsiteCourse table.INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (1050, '123 Smith', 'MTWH', '11:30');INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (1061, '234 Smith', 'TWHF', '13:15');INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (1045, '121 Smith','MWHF', '15:30');INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (4061, '22 Williams', 'TH', '11:15');INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (2042, '225 Adams', 'MTWH', '11:00');INSERT INTO dbo.OnsiteCourse (CourseID, Location, Days, [Time])VALUES (4022, '23 Williams', 'MWF', '9:00');-- Insert data into the CourseInstructor table.INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (1050, 1);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (1061, 31);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (1045, 5);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (2030, 4);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (2021, 27);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (2042, 25);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (4022, 18);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (4041, 32);INSERT INTO dbo.CourseInstructor(CourseID, PersonID)VALUES (4061, 34);GO--Insert data into the OfficeAssignment table.INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (1, '17 Smith');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (4, '29 Adams');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (5, '37 Williams');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (18, '143 Smith');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (25, '57 Adams');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (27, '271 Williams');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (31, '131 Smith');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (32, '203 Williams');INSERT INTO dbo.OfficeAssignment(InstructorID, Location)VALUES (34, '213 Smith');-- Insert data into the StudentGrade table.INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2021, 2, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2030, 2, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2021, 3, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2030, 3, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2021, 6, 2.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2042, 6, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2021, 7, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2042, 7, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2021, 8, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (2042, 8, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 9, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 10, null);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 11, 2.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 12, null);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4061, 12, null);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 14, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 13, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4061, 13, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 14, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 15, 2.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 16, 2);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 17, null);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 19, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4061, 20, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4061, 21, 2);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 22, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4041, 22, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4061, 22, 2.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (4022, 23, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1045, 23, 1.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 24, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 25, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1050, 26, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 26, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 27, 3);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1045, 28, 2.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1050, 28, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 29, 4);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1050, 30, 3.5);INSERT INTO dbo.StudentGrade (CourseID, StudentID, Grade)VALUES (1061, 30, 4);GO

3：RIA之ADO.NET ENTITY DATA MODEL

为web创建ADO.NET ENTITY DATA MODEL，如图：

注意，习惯命名规则：Model数据库名.edmx。

在下一步中，我们选择刚才创建的数据库：

选择新建连接，按照指示完成数据库连接配置。

进入下一步：

在这一步中，注意一定要选择第一个红框中的内容，否则默认不能生成联表查询。在下一步中，我们选择“Generate from database”，如下：

点击Finish后，VS为我们生成了一个以edmx为后缀的文件。OK，到此暂停，我们先来看看这个edmx文件是干什么用的，为我们完成了什么工作。

3.1：什么是EDM

ENTITY DATA MODEL，简写为EDM，中文为实体数据模型。它由三个概念组成。概念模型由概念架构定义语言文件 (.csdl)来定义，映射由映射规范语言文件 (.msl)，存储模型（又称逻辑模型）由存储架构定义语言文件 (.ssdl)来定义。这三者合在一起就是EDM模型。EDM模型在项目中的表现形式就是扩展名为.edmx的文件。

Entity Framework实现了一套类似于ADO.NET2.0中的连接类来操作EDM完成持久化。EntityFramework中所有发往EDM的操作都是经过EntityClient，包括使用LINQ to Entity进行的操作。目前可用操作如下：

4：针对web EMD的测试

理解了EMD在开发中所处的作用，我们就可以针对EDM来写个测试项目。为了简便期间，我们直接在EMD中的SchoolEntities类型的构造方法中直接创建测试（严格意义来说，这不是个单元测试，这仅是测试）。

针对这个操作，会在测试项目中生成一个SchoolEntitiesTest的类型，同时，在这个类型中会生成一个SchoolEntitiesConstructorTest的方法，如下：

由于我们仅仅测试EDM，而跟WEB本身没有关系，所有我们注释掉了红框中的内容。同时我们写入真正的测试代码，如下：

这里的一个小细节是，连接字符串我们通过编码的方式传入到测试方法。EDM的连接字符串和ADO.NET的连接字符串有很大不同，在这里，可公开一下我们的生成EDM连接字符串的方法：

        public string GetConnectionString()        {            string providerName = "System.Data.SqlClient";            string serverName = "192.168.0.96";            string databaseName = "mysample";            SqlConnectionStringBuilder sqlBuilder = new SqlConnectionStringBuilder();            sqlBuilder.DataSource = serverName;            sqlBuilder.InitialCatalog = databaseName;            sqlBuilder.IntegratedSecurity = false;            sqlBuilder.UserID = "sa";            sqlBuilder.Password = "sasa";            string providerString = sqlBuilder.ToString();            EntityConnectionStringBuilder entityBuilder = new EntityConnectionStringBuilder();            entityBuilder.Provider = providerName;            entityBuilder.ProviderConnectionString = providerString;            entityBuilder.Provider = providerName;            entityBuilder.Metadata = "res://*/Modelmysample.csdl|res://*/Modelmysample.ssdl|res://*/Modelmysample.msl";            return entityBuilder.ToString();        }

调试我们的测试代码，最终我们会获取到数据库中的4条记录。

通过了以上的阐述，我们了解了EDM的作用，以及如何测试EDM。接下来，我们需要知道如何在SL APP中调用WEB中的EDM。

5：Domain Service Class

在SL APP中调用EDM是通过WEB的Domain Service Class来实现的。简单的说来，它是RIA SERVICE框架中的一个重要内容。

在WEB选择添加新项，选择Domain Service Class，命名，下一步会出现如下界面：

我们可以做出如上勾选。确定后，编译整个解决方法，会发现目前的解决方案结构会变成如下形式：

注意，第一个红框部分，是VS自动为我们在SL APP生成的。它是第二个红框在客户端的对应版本。我们需要将它包含到项目中去。它包含了所有服务端版本类中定义的方法、实体等，而可在客户端直接调用。

6：Ria Service数据流转

好了，经过以上的描述我们知道了：

EDM：直接操作数据库；

Domain Service Class：调用EDM，并把数据接口通过WCF的形式开放给客户端；

*.Web.g.cs：调用Domain Service Class，完成对数据的读取，并最终呈现给UI；

7：最终展示

在SL APP中的UI调用呈现数据。前台：

后台，直接使用*.Web.g.cs中的DomainServiceMySample 加载数据：

        public MainPage()        {            InitializeComponent();            DomainServiceMySample context = new DomainServiceMySample();            context.Load(context.GetEmpQuery());            lb1.ItemsSource = context.emps;        }

最后界面显示：

8：问题

该示例演示了使用Entity Framework和WCF Ria Services进行Silverlight开发。我们当然可以继续使用此模式完善功能，知道一个功能复杂的应用程序开发完毕。但是，当前，此示例起码存在如下几个问题。

1：实体模型被紧耦合在EDM中，同时它不能项目（模块）使用。随着每一次更新EDM，实体模型会被覆盖；

2：EDM和BLL紧耦合在一起；

3：没有提炼出数据接口，导致我们没有办法在此示例中进行单元测试。示例中虽然存在测试项目，但那是数据库相关的，达不到单元测试的要求；

下篇我们将继续重构该示例，以逐步解决这些问题。

本示例源码下载：SilverlightApplicationSchool20110612.zip