一、OData介绍
开放数据协议（Open Data Protocol，缩写OData）是一种描述如何创建和访问Restful服务的OASIS标准。
二、OData 在asp.net mvc中的用法
1、在vs中新建webApi项目
2、添加测试类型
public class Product { public int Id { get; set; } public string ProductName { get; set; } } 3、开启EF自动迁移，添加EF上下文，
namespace ODataTest.Migrations { using System; using System.Data.Entity; using System.Data.Entity.Migrations; using System.Linq; using ODataTest.Models; internal sealed class Configuration : DbMigrationsConfiguration<ODataTest.Models.EFContext> { public Configuration() { AutomaticMigrationsEnabled = true; AutomaticMigrationDataLossAllowed = true; } protected override void Seed(ODataTest.Models.EFContext context) { // This method will be called after migrating to the latest version. // You can use the DbSet<T>.AddOrUpdate() helper extension method // to avoid creating duplicate seed data. } } } public class EFContext : DbContext { static EFContext() { Database.SetInitializer(new MigrateDatabaseToLatestVersion<EFContext, Configuration>()); } public EFContext() : base("DefaultConnection") { } public DbSet<Product> Products { get; set; } } 4.在数据库添加一些测试数据
Id ProductName
21 产品1
22 产品2
23 产品3
24 产品4
5、在Controllers文件夹添加OData控制器
6、vs将自动生成基本的CURD，
将GetProducts方法的EnableQuery特性的AllowedQueryOptions属性设置为：允许所有查询AllowedQueryOptions.All
public class ProductsController : ODataController { private EFContext db = new EFContext(); // GET: odata/Products [EnableQuery(AllowedQueryOptions = AllowedQueryOptions.All)] public IQueryable<Product> GetProducts() { return db.Products; } // GET: odata/Products(5) [EnableQuery] public SingleResult<Product> GetProduct([FromODataUri] int key) { return SingleResult.Create(db.Products.Where(product => product.Id == key)); } // PUT: odata/Products(5) public IHttpActionResult Put([FromODataUri] int key, Delta<Product> patch) { Validate(patch.GetEntity()); if (!ModelState.IsValid) { return BadRequest(ModelState); } Product product = db.Products.Find(key); if (product == null) { return NotFound(); } patch.Put(product); try { db.SaveChanges(); } catch (DbUpdateConcurrencyException) { if (!ProductExists(key)) { return NotFound(); } else { throw; } } return Updated(product); } // POST: odata/Products public IHttpActionResult Post(Product product) { if (!ModelState.IsValid) { return BadRequest(ModelState); } db.Products.Add(product); db.SaveChanges(); return Created(product); } // PATCH: odata/Products(5) [AcceptVerbs("PATCH", "MERGE")] public IHttpActionResult Patch([FromODataUri] int key, Delta<Product> patch) { Validate(patch.GetEntity()); if (!ModelState.IsValid) { return BadRequest(ModelState); } Product product = db.Products.Find(key); if (product == null) { return NotFound(); } patch.Patch(product); try { db.SaveChanges(); } catch (DbUpdateConcurrencyException) { if (!ProductExists(key)) { return NotFound(); } else { throw; } } return Updated(product); } // DELETE: odata/Products(5) public IHttpActionResult Delete([FromODataUri] int key) { Product product = db.Products.Find(key); if (product == null) { return NotFound(); } db.Products.Remove(product); db.SaveChanges(); return StatusCode(HttpStatusCode.NoContent); } protected override void Dispose(bool disposing) { if (disposing) { db.Dispose(); } base.Dispose(disposing); } private bool ProductExists(int key) { return db.Products.Count(e => e.Id == key) > 0; } } 7、在WebApiConfig类的Register方法里面注册OData路由
using System.Web.Http; using System.Web.Http.OData.Builder; using System.Web.Http.OData.Extensions; using ODataTest.Models; ODataConventionModelBuilder builder = new ODataConventionModelBuilder(); builder.EntitySet<Product>("Products"); config.Routes.MapODataServiceRoute("odata", "odata", builder.GetEdmModel()); 8、运行网站就可以在浏览器就行OData的API测试
查询所有：http://localhost:64643/odata/Products
相等查询：http://localhost:64643/odata/Products?$filter=ProductName eq '产品1'
还有更多的查询，参考，http://www.odata.org/documentation/odata-version-3-0/url-conventions/