在上一篇(WCF学习之旅—实现REST服务(二十二))文章中简单介绍了一下RestFul与WCF支持RestFul所提供的方法,本文讲解一下如何创建一个支持REST的WCF服务端程序。
四、在WCF中创建REST服务
1. 在SCF.Contracts 在创建一个服务契约IBookRestService.
这里提供两个方法,分别采用GET和POST方式访问。
我们可以看到,与普通WCF服务契约不同的是,需要额外用WebGet或者WebInvoke指定REST访问的方式。另外还要指定消息包装样式和消息格式,默认的消息请求和响应格式为XML,若选择JSON需要显式声明。
UriTemplate用来将方法映射到具体的Uri上,但如果不指定映射,将映射到默认的Uri。比如采用Get访问的GetBook方法,默认映射是:/ GetBook?BookId={BookId}。
在编写代码的过程中,会出现如下图中1的错误,请引用下图2处的
using SCF.Model; using System; using System.Collections.Generic; using System.Linq; using System.ServiceModel; using System.ServiceModel.Web; using System.Text; using System.Threading.Tasks; namespace SCF.Contracts { [DataContractFormat] [ServiceContract] public interface IBookRestService { //[WebGet(UriTemplate = "/Books/Get/{BookId}/{categroy}", BodyStyle = WebMessageBodyStyle.Bare, ResponseFormat = WebMessageFormat.Json)] [WebGet(UriTemplate = "/Books/Get/{BookId}", BodyStyle = WebMessageBodyStyle.Bare)] [OperationContract] ListGetBook(string BookId); //[WebInvoke(Method = "POST", UriTemplate = "/Books/Create", BodyStyle = WebMessageBodyStyle.Bare, ResponseFormat = WebMessageFormat.Json, RequestFormat = WebMessageFormat.Json)] [WebInvoke(Method = "POST", UriTemplate = "/Books/Add", BodyStyle = WebMessageBodyStyle.Bare)] [OperationContract] Result AddBook(Books book); } }
2. 在项目SCF.Model中创建一个实体对象Books与一个返回对象Result,用作数据传输的载体,下面是Books.cs的内容
namespace SCF.Model { using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations; using System.ComponentModel.DataAnnotations.Schema; using System.Data.Entity.Spatial; using System.Runtime.Serialization; ///DataContract 数据契约:服务端和客户端之间要传送的自定义数据类型 [DataContract(Namespace = "http://tempuri.org/")] public partial class Books { ////// 在数据传送过程中,只有成员变量可以被传送而成员方法不可以。 /// 并且只有当成员变量加上DataMember时才可以被序列进行数据传输, /// 如果不加DataMember,客户端将无法获得该属性的任何信息 /// [DataMember] [Key] public int BookID { get; set; } [DataMember] [Required] public string Category { get; set; } [DataMember] [Required] public string Name { get; set; } [DataMember] public int Numberofcopies { get; set; } [DataMember] public int AuthorID { get; set; } [DataMember] public decimal Price { get; set; } [DataMember] public DateTime PublishDate { get; set; } [StringLength(5)] [DataMember] public string Rating { get; set; } } } using System; using System.Collections.Generic; using System.Linq; using System.Runtime.Serialization; using System.Text; using System.Threading.Tasks; namespace SCF.Model { [DataContract(Namespace = "http://tempuri.org/")] public class Result { [DataMember] public string Message { get; set; } } }
3. 在SCF.WcfService项目中实现在SCF.Contracts项目中定义的服务契约。这里最简单的实现GetBook和AddBook两个方法的逻辑。
using SCF.Contracts; using System; using System.Collections.Generic; using System.Linq; using System.Runtime.Serialization; using System.ServiceModel; using System.Text; using SCF.Model; using SCF.Common; namespace SCF.WcfService { // 注意: 使用“重构”菜单上的“重命名”命令,可以同时更改代码、svc 和配置文件中的类名“BookRestService”。 // 注意: 为了启动 WCF 测试客户端以测试此服务,请在解决方案资源管理器中选择 BookRestService.svc 或 BookRestService.svc.cs,然后开始调试。 public class BookRestService : IBookRestService { Entities db = new Entities(); public Result AddBook(Books book) { Result result = new Result(); try { db.Books.Add(book); db.SaveChanges(); result.Message = string.Format("书名:{0} 已经添加!",book.Name); } catch (Exception ex) { result.Message =ex.Message; } return result; } public ListGetBook(string BookId) { var cateLst = new List<string>(); var cateQry = from d in db.Books orderby d.Category select d.Category; cateLst.AddRange(cateQry.Distinct()); var books = from m in db.Books select m; if (!String.IsNullOrEmpty(BookId)) { books = books.Where(s => s.Name.Contains(BookId)); } List list = null; list = books.ToList (); return list; } } }
4. 在配置文件在中配置我们的Rest服务,必须使用WebHttpBehavior对服务的终结点进行配置。
xml version="1.0" encoding="utf-8"?> <configuration> <configSections> <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework,
Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /> configSections> <entityFramework> <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" /> <providers> <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" /> providers> entityFramework> <system.serviceModel> <bindings> <webHttpBinding> <binding name="RestWebBinding"> binding> webHttpBinding> bindings> <behaviors> <serviceBehaviors> <behavior name="metadataBehavior"> <serviceMetadata httpGetEnabled="true" httpGetUrl="http://127.0.0.1:8888/BookService/metadata" /> <serviceDebug includeExceptionDetailInFaults="True" /> behavior> <behavior name="RestServiceBehavior"> behavior> serviceBehaviors> <endpointBehaviors> <behavior name="RestWebBehavior"> <webHttp /> behavior> endpointBehaviors> behaviors> <services> <service behaviorConfiguration="metadataBehavior" name="SCF.WcfService.BookService"> <endpoint address="http://127.0.0.1:8888/BookService" binding="wsHttpBinding" contract="SCF.Contracts.IBookService" /> service> <service name="SCF.WcfService.BookRestService" behaviorConfiguration="RestServiceBehavior"> <endpoint address="http://127.0.0.1:8888/" behaviorConfiguration="RestWebBehavior" binding="webHttpBinding" bindingConfiguration="RestWebBinding" contract="SCF.Contracts.IBookRestService"> endpoint> service> services> system.serviceModel> <startup> <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" /> startup> <connectionStrings> <add name="Entities" connectionString="metadata=res://*/BookModel.csdl|res://*/BookModel.ssdl|res://*/BookModel.msl;
provider=System.Data.SqlClient;provider connection string="data source=.\SQLEXPRESS;initial catalog=Test;
integrated security=SSPI;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" /> connectionStrings> configuration>