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]
List<Books> GetBook(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
{
/// <summary>
/// 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
/// </summary>
[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 List<Books> GetBook(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<Books> list = null;
list = books.ToList<Books>();
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>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<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">
<!--这里必须设置-->
<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>