[索引页]
[源码下载]
作者: webabcd
介绍
以Northwind为示例数据库,演示ADO.NET Data Services(数据服务)
示例
服务端
Service.cs
本文转自webabcd 51CTO博客,原文链接:http://blog.51cto.com/webabcd/341567,如需转载请自行联系原作者
[源码下载]
再接再厉VS 2008 sp1 + .NET 3.5 sp1(7) - Data Services(数据服务)
作者: webabcd
介绍
以Northwind为示例数据库,演示ADO.NET Data Services(数据服务)
- DataService<T> - ADO.NET 数据服务的主入口点。 T 为数据源类名
- IDataServiceConfiguration.SetEntitySetAccessRule(string name, EntitySetRights rights) - 为指定实体集设置访问规则
- QueryInterceptorAttribute - 声明在方法上的查询拦截器
- DataServiceContext - 数据服务的上下文
- DataServiceQuery - 以指定的 URI 语法查询数据服务
示例
服务端
Service.cs
using System;
using System.Data.Services;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel.Web;
using VS2008SP1.Business;
using System.Linq.Expressions;
// DataService<T> - ADO.NET 数据服务的主入口点。 T 为数据源类名
public class Service : DataService<VS2008SP1.Business.NorthwindEntities>
{
// 初始化涉及服务范围的策略(仅调用一次)
static void InitializeService() static void InitializeService(IDataServiceConfiguration config)
{
/**//*
* IDataServiceConfiguration.SetEntitySetAccessRule( string name, EntitySetRights rights) - 为指定实体集设置访问规则
* name - 实体集名称(* 为全部)
* rights - 设置对指定实体集的操作权限 [System.Data.Services.EntitySetRights 枚举]
* EntitySetRights.None - 权限为:无任何权限
* EntitySetRights.All - 权限为:全部权限
* EntitySetRights.ReadSingle - 权限为:只能读取数据集内的某一条数据
* EntitySetRights.ReadMultiple - 权限为:可读取数据集内的全部数据
* EntitySetRights.WriteAppend - 权限为:插入
* EntitySetRights.WriteReplace - 权限为:更新
* EntitySetRights.WriteDelete - 权限为:删除
* EntitySetRights.WriteMerge - 权限为:合并数据
* EntitySetRights.AllRead - 权限为:全部可读
* EntitySetRights.AllWrite - 权限为:全部可写
*/
config.SetEntitySetAccessRule( "*", EntitySetRights.All);
// config.SetEntitySetAccessRule( "*", EntitySetRights.AllRead | EntitySetRights.AllWrite);
}
/**//*
* QueryInterceptorAttribute - 声明在方法上的查询拦截器
* 方法名任意(不带参数),返回值必须为一个 Expression<Func<T, bool>> 表达式,T 为需要过滤的实体集类名
*/
[QueryInterceptor( "Orders")]
Expression<Func<Orders, bool>> FilterOrders() Expression<Func<Orders, bool>> FilterOrders()
{
// 本例为无论在任何情况下,返回的 Orders 都是 ContactName 为 Paul Henriot 的 Orders
return o => o.Customers.ContactName == "Paul Henriot";
}
}
using System.Data.Services;
using System.Collections.Generic;
using System.Linq;
using System.ServiceModel.Web;
using VS2008SP1.Business;
using System.Linq.Expressions;
// DataService<T> - ADO.NET 数据服务的主入口点。 T 为数据源类名
public class Service : DataService<VS2008SP1.Business.NorthwindEntities>
{
// 初始化涉及服务范围的策略(仅调用一次)
static void InitializeService() static void InitializeService(IDataServiceConfiguration config)
{
/**//*
* IDataServiceConfiguration.SetEntitySetAccessRule( string name, EntitySetRights rights) - 为指定实体集设置访问规则
* name - 实体集名称(* 为全部)
* rights - 设置对指定实体集的操作权限 [System.Data.Services.EntitySetRights 枚举]
* EntitySetRights.None - 权限为:无任何权限
* EntitySetRights.All - 权限为:全部权限
* EntitySetRights.ReadSingle - 权限为:只能读取数据集内的某一条数据
* EntitySetRights.ReadMultiple - 权限为:可读取数据集内的全部数据
* EntitySetRights.WriteAppend - 权限为:插入
* EntitySetRights.WriteReplace - 权限为:更新
* EntitySetRights.WriteDelete - 权限为:删除
* EntitySetRights.WriteMerge - 权限为:合并数据
* EntitySetRights.AllRead - 权限为:全部可读
* EntitySetRights.AllWrite - 权限为:全部可写
*/
config.SetEntitySetAccessRule( "*", EntitySetRights.All);
// config.SetEntitySetAccessRule( "*", EntitySetRights.AllRead | EntitySetRights.AllWrite);
}
/**//*
* QueryInterceptorAttribute - 声明在方法上的查询拦截器
* 方法名任意(不带参数),返回值必须为一个 Expression<Func<T, bool>> 表达式,T 为需要过滤的实体集类名
*/
[QueryInterceptor( "Orders")]
Expression<Func<Orders, bool>> FilterOrders() Expression<Func<Orders, bool>> FilterOrders()
{
// 本例为无论在任何情况下,返回的 Orders 都是 ContactName 为 Paul Henriot 的 Orders
return o => o.Customers.ContactName == "Paul Henriot";
}
}
1、添加、查询、更新和删除的Demo
Demo.aspx
Demo.aspx
<%@ Page Title=
"添加、查询、更新和删除的Demo" Language=
"C#" MasterPageFile=
"~/Site.master" AutoEventWireup=
"true"
CodeFile= "Demo.aspx.cs" Inherits= "DataServices_Demo" %>
<asp:Content ID= "Content1" ContentPlaceHolderID= "head" runat= "Server">
</asp:Content>
<asp:Content ID= "Content2" ContentPlaceHolderID= "ContentPlaceHolder1" runat= "Server">
<div style= "margin: 10px;">
CategoryName:<asp:TextBox ID= "txtCategoryName" runat= "server" />
Description:<asp:TextBox ID= "txtDescription" runat= "server" />
<asp:Button ID= "btnAddCategory" runat= "server" Text= "添加产品类别" OnClick= "btnAddCategory_Click" />
</div>
<div style= "margin: 10px;">
<asp:GridView ID= "GridView1" DataKeyNames= "CategoryID" runat= "server" AutoGenerateColumns= "false"
OnRowDeleting= "GridView1_RowDeleting" OnRowCancelingEdit= "GridView1_RowCancelingEdit"
OnRowEditing= "GridView1_RowEditing" OnRowUpdating= "GridView1_RowUpdating" OnSelectedIndexChanged= "GridView1_SelectedIndexChanged">
<Columns>
<asp:BoundField DataField= "CategoryID" HeaderText= "ID" ReadOnly= "true" />
<asp:BoundField DataField= "CategoryName" HeaderText= "CategoryName" />
<asp:BoundField DataField= "Description" HeaderText= "Description" />
<asp:CommandField ShowSelectButton= "True" ShowEditButton= "True" ShowDeleteButton= "True">
</asp:CommandField>
</Columns>
</asp:GridView>
</div>
<div style= "margin: 10px;">
<asp:GridView ID= "GridView2" runat= "server">
</asp:GridView>
</div>
</asp:Content>
CodeFile= "Demo.aspx.cs" Inherits= "DataServices_Demo" %>
<asp:Content ID= "Content1" ContentPlaceHolderID= "head" runat= "Server">
</asp:Content>
<asp:Content ID= "Content2" ContentPlaceHolderID= "ContentPlaceHolder1" runat= "Server">
<div style= "margin: 10px;">
CategoryName:<asp:TextBox ID= "txtCategoryName" runat= "server" />
Description:<asp:TextBox ID= "txtDescription" runat= "server" />
<asp:Button ID= "btnAddCategory" runat= "server" Text= "添加产品类别" OnClick= "btnAddCategory_Click" />
</div>
<div style= "margin: 10px;">
<asp:GridView ID= "GridView1" DataKeyNames= "CategoryID" runat= "server" AutoGenerateColumns= "false"
OnRowDeleting= "GridView1_RowDeleting" OnRowCancelingEdit= "GridView1_RowCancelingEdit"
OnRowEditing= "GridView1_RowEditing" OnRowUpdating= "GridView1_RowUpdating" OnSelectedIndexChanged= "GridView1_SelectedIndexChanged">
<Columns>
<asp:BoundField DataField= "CategoryID" HeaderText= "ID" ReadOnly= "true" />
<asp:BoundField DataField= "CategoryName" HeaderText= "CategoryName" />
<asp:BoundField DataField= "Description" HeaderText= "Description" />
<asp:CommandField ShowSelectButton= "True" ShowEditButton= "True" ShowDeleteButton= "True">
</asp:CommandField>
</Columns>
</asp:GridView>
</div>
<div style= "margin: 10px;">
<asp:GridView ID= "GridView2" runat= "server">
</asp:GridView>
</div>
</asp:Content>
Demo.aspx.cs
// 客户端用到的只有以下两个类
// System.Data.Services.Client.DataServiceContext - 数据服务的上下文
// System.Data.Services.Client.DataServiceQuery - 以指定的 URI 语法查询数据服务
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using MyDataService;
public partial class DataServices_Demo : System.Web.UI.Page
{
// ADO.NET 数据服务的地址
Uri _uri = new Uri( "http://localhost:7002/DataServices/Service.svc/", UriKind.Absolute);
void Page_Load() void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
BindData();
}
}
void BindData()
{
// NorthwindEntities - 继承自 DataServiceContext ,其构造函数的参数为数据服务的 URI 地址
NorthwindEntities ctx = new NorthwindEntities(_uri);
// 将 System.Data.Services.Client.DataServiceQuery<Categories> 绑定到 Gridview1
GridView1.DataSource = ctx.Categories;
GridView1.DataBind();
}
void btnAddCategory_Click() void btnAddCategory_Click(object sender, EventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
Categories category = new Categories();
category.CategoryName = txtCategoryName.Text;
category.Description = txtDescription.Text;
// DataServiceContext.Timeout - 超时时间
// DataServiceContext.MergeOption - 当前数据上下文与数据服务的数据的同步选项 [System.Data.Services.Client.MergeOption 枚举]
// AppendOnly - 追加。默认值
// OverwriteChanges - 以新结果为准
// PreserveChanges - 以原结果为准
// NoTracking - 取消变更跟踪,不会使用 ObjectStateManager,减少执行查询的时间,所有返回的实体将是分离的状态(detached state)
ctx.MergeOption = System.Data.Services.Client.MergeOption.AppendOnly;
ctx.AddToCategories(category);
for (int i = 0; i < 10; i++)
{
var product = new Products() { ProductName = "测试用" + i.ToString() };
product.Categories = category;
ctx.AddToProducts(product);
// DataServiceContext.SetLink(Object source, string sourceProperty, Object target) - 在指定对象上创建新的连接,Added状态,SaveChanges() 的时候会一起发送到数据服务。多对一关系
// source - 源对象
// sourceProperty - 源对象上的属性,用于标识目标对象的类型
// target - 目标对象
ctx.SetLink(product, "Categories", category);
// DataServiceContext.AddLink(Object source, string sourceProperty, Object target) - 在指定对象上创建新的连接,Added状态,SaveChanges() 的时候会一起发送到数据服务。一对多关系
// DataServiceContext.DeleteLink(Object source, string sourceProperty, Object target) - 在指定的对象上删除连接,Deleted状态,SaveChanges() 的时候会一起发送到数据服务
}
// DataServiceContext.SaveChanges() - 将所有更新保存到相关存储区中
// SaveChangesOptions.Batch - 一个 http 提交所有操作
// SaveChangesOptions.ContinueOnError - 一个 http 一个操作,某操作出错仍将处理后续操作(不能与 Batch 共存)
// SaveChangesOptions.ReplaceOnUpdate -
// SaveChangesOptions.None - 出错则停止
ctx.SaveChanges(System.Data.Services.Client.SaveChangesOptions.Batch);
Page.ClientScript.RegisterStartupScript(this.GetType(), "js", "alert('CategoryID: " + category.CategoryID + "');", true);
GridView1.EditIndex = -1;
BindData();
}
void GridView1_RowDeleting() void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.DataKeys[e.RowIndex].Value;
var category = ctx.Categories.Where(p => p.CategoryID == categoryId).First();
// DataServiceContext.LoadProperty(Object entity, string propertyName) - 加载指定对象的指定实体属性
// entity - 包含要加载的实体属性的实体
// propertyName - 需要加载的实体属性的名称
ctx.LoadProperty(category, "Products");
foreach (var product in category.Products)
{
ctx.DeleteObject(product);
}
ctx.DeleteObject(category);
ctx.SaveChanges();
GridView1.EditIndex = -1;
BindData();
}
void GridView1_SelectedIndexChanged() void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.SelectedDataKey.Value;
// 查找当前选中的类别下的产品集合
var products = ctx.Products.Where(p => p.Categories.CategoryID == categoryId);
// 将 System.Linq.IQueryable<Products> 绑定到 GridView2
GridView2.DataSource = products;
GridView2.DataBind();
}
void GridView1_RowUpdating() void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.DataKeys[e.RowIndex].Value;
var category = ctx.Categories.Where(p => p.CategoryID == categoryId).First();
category.CategoryName = ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text;
category.Description = ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text;
ctx.UpdateObject(category);
ctx.SaveChanges();
GridView1.EditIndex = -1;
BindData();
}
void GridView1_RowEditing() void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
BindData();
}
void GridView1_RowCancelingEdit() void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
BindData();
}
}
// System.Data.Services.Client.DataServiceContext - 数据服务的上下文
// System.Data.Services.Client.DataServiceQuery - 以指定的 URI 语法查询数据服务
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using MyDataService;
public partial class DataServices_Demo : System.Web.UI.Page
{
// ADO.NET 数据服务的地址
Uri _uri = new Uri( "http://localhost:7002/DataServices/Service.svc/", UriKind.Absolute);
void Page_Load() void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
BindData();
}
}
void BindData()
{
// NorthwindEntities - 继承自 DataServiceContext ,其构造函数的参数为数据服务的 URI 地址
NorthwindEntities ctx = new NorthwindEntities(_uri);
// 将 System.Data.Services.Client.DataServiceQuery<Categories> 绑定到 Gridview1
GridView1.DataSource = ctx.Categories;
GridView1.DataBind();
}
void btnAddCategory_Click() void btnAddCategory_Click(object sender, EventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
Categories category = new Categories();
category.CategoryName = txtCategoryName.Text;
category.Description = txtDescription.Text;
// DataServiceContext.Timeout - 超时时间
// DataServiceContext.MergeOption - 当前数据上下文与数据服务的数据的同步选项 [System.Data.Services.Client.MergeOption 枚举]
// AppendOnly - 追加。默认值
// OverwriteChanges - 以新结果为准
// PreserveChanges - 以原结果为准
// NoTracking - 取消变更跟踪,不会使用 ObjectStateManager,减少执行查询的时间,所有返回的实体将是分离的状态(detached state)
ctx.MergeOption = System.Data.Services.Client.MergeOption.AppendOnly;
ctx.AddToCategories(category);
for (int i = 0; i < 10; i++)
{
var product = new Products() { ProductName = "测试用" + i.ToString() };
product.Categories = category;
ctx.AddToProducts(product);
// DataServiceContext.SetLink(Object source, string sourceProperty, Object target) - 在指定对象上创建新的连接,Added状态,SaveChanges() 的时候会一起发送到数据服务。多对一关系
// source - 源对象
// sourceProperty - 源对象上的属性,用于标识目标对象的类型
// target - 目标对象
ctx.SetLink(product, "Categories", category);
// DataServiceContext.AddLink(Object source, string sourceProperty, Object target) - 在指定对象上创建新的连接,Added状态,SaveChanges() 的时候会一起发送到数据服务。一对多关系
// DataServiceContext.DeleteLink(Object source, string sourceProperty, Object target) - 在指定的对象上删除连接,Deleted状态,SaveChanges() 的时候会一起发送到数据服务
}
// DataServiceContext.SaveChanges() - 将所有更新保存到相关存储区中
// SaveChangesOptions.Batch - 一个 http 提交所有操作
// SaveChangesOptions.ContinueOnError - 一个 http 一个操作,某操作出错仍将处理后续操作(不能与 Batch 共存)
// SaveChangesOptions.ReplaceOnUpdate -
// SaveChangesOptions.None - 出错则停止
ctx.SaveChanges(System.Data.Services.Client.SaveChangesOptions.Batch);
Page.ClientScript.RegisterStartupScript(this.GetType(), "js", "alert('CategoryID: " + category.CategoryID + "');", true);
GridView1.EditIndex = -1;
BindData();
}
void GridView1_RowDeleting() void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.DataKeys[e.RowIndex].Value;
var category = ctx.Categories.Where(p => p.CategoryID == categoryId).First();
// DataServiceContext.LoadProperty(Object entity, string propertyName) - 加载指定对象的指定实体属性
// entity - 包含要加载的实体属性的实体
// propertyName - 需要加载的实体属性的名称
ctx.LoadProperty(category, "Products");
foreach (var product in category.Products)
{
ctx.DeleteObject(product);
}
ctx.DeleteObject(category);
ctx.SaveChanges();
GridView1.EditIndex = -1;
BindData();
}
void GridView1_SelectedIndexChanged() void GridView1_SelectedIndexChanged(object sender, EventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.SelectedDataKey.Value;
// 查找当前选中的类别下的产品集合
var products = ctx.Products.Where(p => p.Categories.CategoryID == categoryId);
// 将 System.Linq.IQueryable<Products> 绑定到 GridView2
GridView2.DataSource = products;
GridView2.DataBind();
}
void GridView1_RowUpdating() void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
var categoryId = (int)GridView1.DataKeys[e.RowIndex].Value;
var category = ctx.Categories.Where(p => p.CategoryID == categoryId).First();
category.CategoryName = ((TextBox)GridView1.Rows[e.RowIndex].Cells[1].Controls[0]).Text;
category.Description = ((TextBox)GridView1.Rows[e.RowIndex].Cells[2].Controls[0]).Text;
ctx.UpdateObject(category);
ctx.SaveChanges();
GridView1.EditIndex = -1;
BindData();
}
void GridView1_RowEditing() void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
BindData();
}
void GridView1_RowCancelingEdit() void GridView1_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
BindData();
}
}
2、其他知识点
Demo2.aspx
Demo2.aspx
<%@ Page Title=
"其它" Language=
"C#" MasterPageFile=
"~/Site.master" AutoEventWireup=
"true"
CodeFile= "Demo2.aspx.cs" Inherits= "DataServices_Demo2" %>
<asp:Content ID= "Content1" ContentPlaceHolderID= "head" runat= "Server">
</asp:Content>
<asp:Content ID= "Content2" ContentPlaceHolderID= "ContentPlaceHolder1" runat= "Server">
<div id= "result" runat= "server">
</div>
</asp:Content>
CodeFile= "Demo2.aspx.cs" Inherits= "DataServices_Demo2" %>
<asp:Content ID= "Content1" ContentPlaceHolderID= "head" runat= "Server">
</asp:Content>
<asp:Content ID= "Content2" ContentPlaceHolderID= "ContentPlaceHolder1" runat= "Server">
<div id= "result" runat= "server">
</div>
</asp:Content>
Demo2.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using MyDataService;
using System.Data.Services.Client;
public partial class DataServices_Demo2 : System.Web.UI.Page
{
// ADO.NET 数据服务的地址
Uri _uri = new Uri( "http://localhost:7002/DataServices/Service.svc/", UriKind.Absolute);
void Page_Load() void Page_Load(object sender, EventArgs e)
{
// 以 URI 语法的方式查询 ADO.NET 数据服务
Demo();
// 异步方式查询 ADO.NET 数据服务
Demo2();
// 演示查询拦截器的 Demo
Demo3();
// 演示以 JSON 作为响应格式的 Demo
Demo4();
}
void Demo()
{
DataServiceContext ctx = new DataServiceContext(_uri);
// 以 URI 语法的方式查询 ADO.NET 数据服务,详细语法参看 MSDN
// http://[Url]/[ServiceName]/[EntityName]/[NavigationOptions]?[QueryOptions]
DataServiceQuery<Categories> categories = ctx.CreateQuery<Categories>( "/Categories");
foreach (var c in categories)
{
result.InnerHtml += c.CategoryID + ",";
}
result.InnerHtml += "<br /><br />";
}
void Demo2()
{
DataServiceContext ctx = new DataServiceContext(_uri);
DataServiceQuery<Categories> query = ctx.CreateQuery<Categories>( "/Categories");
// 异步方式查询 ADO.NET 数据服务
query.BeginExecute(
delegate(IAsyncResult ar)
{
foreach (var c in query.EndExecute(ar))
{
result.InnerHtml += c.CategoryID + ",";
}
result.InnerHtml += "<br /><br />";
},
null);
}
void Demo3()
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
// 因为设置了查询拦截器,所以只能收到 ContactName 为 Paul Henriot 的 Orders
foreach (var o in ctx.Orders)
{
result.InnerHtml += o.OrderID + ",";
}
result.InnerHtml += "<br /><br />";
}
void Demo4()
{
System.Net.WebClient client = new System.Net.WebClient();
// 需要以 json 格式返回结果的话,需要设置以下 header
client.Headers.Add( "accept", "application/json");
// client.Headers.Add( "accept", "application/xml"); xml/atom 格式
// client.Headers.Add( "accept", "*/*"); xml/atom 格式,默认值
result.InnerHtml += HttpUtility.HtmlEncode(client.DownloadString(_uri));
}
}
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using MyDataService;
using System.Data.Services.Client;
public partial class DataServices_Demo2 : System.Web.UI.Page
{
// ADO.NET 数据服务的地址
Uri _uri = new Uri( "http://localhost:7002/DataServices/Service.svc/", UriKind.Absolute);
void Page_Load() void Page_Load(object sender, EventArgs e)
{
// 以 URI 语法的方式查询 ADO.NET 数据服务
Demo();
// 异步方式查询 ADO.NET 数据服务
Demo2();
// 演示查询拦截器的 Demo
Demo3();
// 演示以 JSON 作为响应格式的 Demo
Demo4();
}
void Demo()
{
DataServiceContext ctx = new DataServiceContext(_uri);
// 以 URI 语法的方式查询 ADO.NET 数据服务,详细语法参看 MSDN
// http://[Url]/[ServiceName]/[EntityName]/[NavigationOptions]?[QueryOptions]
DataServiceQuery<Categories> categories = ctx.CreateQuery<Categories>( "/Categories");
foreach (var c in categories)
{
result.InnerHtml += c.CategoryID + ",";
}
result.InnerHtml += "<br /><br />";
}
void Demo2()
{
DataServiceContext ctx = new DataServiceContext(_uri);
DataServiceQuery<Categories> query = ctx.CreateQuery<Categories>( "/Categories");
// 异步方式查询 ADO.NET 数据服务
query.BeginExecute(
delegate(IAsyncResult ar)
{
foreach (var c in query.EndExecute(ar))
{
result.InnerHtml += c.CategoryID + ",";
}
result.InnerHtml += "<br /><br />";
},
null);
}
void Demo3()
{
NorthwindEntities ctx = new NorthwindEntities(_uri);
// 因为设置了查询拦截器,所以只能收到 ContactName 为 Paul Henriot 的 Orders
foreach (var o in ctx.Orders)
{
result.InnerHtml += o.OrderID + ",";
}
result.InnerHtml += "<br /><br />";
}
void Demo4()
{
System.Net.WebClient client = new System.Net.WebClient();
// 需要以 json 格式返回结果的话,需要设置以下 header
client.Headers.Add( "accept", "application/json");
// client.Headers.Add( "accept", "application/xml"); xml/atom 格式
// client.Headers.Add( "accept", "*/*"); xml/atom 格式,默认值
result.InnerHtml += HttpUtility.HtmlEncode(client.DownloadString(_uri));
}
}
OK
[源码下载]
[源码下载]
本文转自webabcd 51CTO博客,原文链接:http://blog.51cto.com/webabcd/341567,如需转载请自行联系原作者