精进不休 .NET 4.0 (2) - asp.net 4.0 新特性之url路由

  1. 云栖社区>
  2. 博客>
  3. 正文

精进不休 .NET 4.0 (2) - asp.net 4.0 新特性之url路由

技术小胖子 2017-11-10 00:36:00 浏览1073
展开阅读全文
[索引页]
[源码下载]


精进不休 .NET 4.0 (2) - asp.net 4.0 新特性之url路由, 自定义CacheProvider, 新增的表达式<%: expression %>, QueryExtender控件, 其它新特性


作者:webabcd


介绍
asp.net 4.0 的新增功能
  • 在 web form 中做 url 路由 
  • 通过实现自定义的 CacheProvider ,来实现自定义的页面缓存逻辑 
  • 新增的表达式 <%: expression %> 相当于 <%= HttpUtility.HtmlEncode(expression) %> 
  • 控件 QueryExtender,对数据源控件获得的数据做再检索 
  • 其它新特性


示例
1、web form 中的 url 路由的 demo
Global.asax.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.Security; 
using System.Web.SessionState; 

using System.Web.Routing; 

namespace AspDotNet 

        public class Global : System.Web.HttpApplication 
        { 
void Application_Start() void Application_Start(object sender, EventArgs e) 
                { 
                        // 关于 Routing 可以参考以前写的 http://webabcd.blog.51cto.com/1787395/341116 
                        // 其中 PageRouteHandler 类的作用是将 URL 路由的功能集成到 Web Form 中 
                        RouteTable.Routes.Add("myRoute"new Route("user/{userName}/{age}"new PageRouteHandler("~/UrlRouting/Default.aspx"))); 

                        /* 对应的配置如下,在 machine.config 中 
                        <system.web> 
                             <httpmodule> 
                                        <add name="RoutingModule" type="System.Web.Routing.UrlRoutingModule"/>    
                             </httpmodule> 
                        <system.web> 
                         */ 
                } 
        } 
}
 
UrlRouting/Default.aspx
<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true
        CodeBehind="Default.aspx.cs" Inherits="AspDotNet.UrlRouting.Default" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
        <!-- 
                在页面上获取 url 路由而来的数据的方法 
                配合以下逻辑的路由规则是:"user/{userName}/{age}" 
        --> 
        <asp:Literal runat="server" Text="<%$ RouteValue:userName%>" /> 
        <br /> 
        <asp:Literal runat="server" Text="<%$ RouteValue:age%>" /> 

        <!-- 
                另外,对于数据源控件来说,也多了一种参数类型 RouteParameter    
        --> 
</asp:Content> 
<%-- 
对应的配置如下,在 machine.config 中 
<system.web> 
     <compilation debug="true" targetFrameworkMoniker=".NETFramework,Version=v4.0"
            <expressionBuilders> 
                 <add expressionPrefix="RouteValue" type="System.Web.Compilation.RouteValueExpressionBuilder" /> 
            </expressionBuilders> 
     </compilation> 
<system.web> 
--%> 
 
UrlRouting/Default.aspx.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

namespace AspDotNet.UrlRouting 

        public partial class Default : System.Web.UI.Page 
        { 
void Page_Load() void Page_Load(object sender, EventArgs e) 
                { 
                        // 获取 url 路由而来的数据 
                        // 配合以下逻辑的路由规则是:"user/{userName}/{age}" 
                        Response.Write("userName: " + RouteData.Values["userName"].ToString()); 
                        Response.Write("<br />"); 
                        Response.Write("age: " + RouteData.Values["age"].ToString()); 
                } 
        } 

 
UrlRouting/RouteUrlExpressionBuilderDemo.aspx
<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true
        CodeBehind="RouteUrlExpressionBuilderDemo.aspx.cs" Inherits="AspDotNet.UrlRouting.RouteUrlExpressionBuilderDemo" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
        <!-- 
                在页面上构造 url 路由的方式 
        --> 
        <asp:HyperLink ID="lnk1" runat="server" NavigateUrl="<%$ RouteUrl:RouteName=myRoute, userName=webabcd, age=30 %>" 
                Text="goto" /> 
        <br /><br /> 
        <asp:HyperLink ID="lnk2" runat="server" Text="goto" /> 
</asp:Content> 
<%-- 
对应的配置如下,在 machine.config 中 
<system.web> 
     <compilation debug="true" targetFrameworkMoniker=".NETFramework,Version=v4.0"
            <expressionBuilders> 
                 <add expressionPrefix="RouteUrl" type="System.Web.Compilation.RouteUrlExpressionBuilder"/> 
            </expressionBuilders> 
     </compilation> 
<system.web> 
--%>
 
UrlRouting/RouteUrlExpressionBuilderDemo.aspx.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

using System.Web.Compilation; 

namespace AspDotNet.UrlRouting 

        public partial class RouteUrlExpressionBuilderDemo : System.Web.UI.Page 
        { 
void Page_Load() void Page_Load(object sender, EventArgs e) 
                { 
                        // 在代码中构造 url 路由的方式 
                        string expression = String.Format("RouteName={0}, userName={1}, age={2}""myRoute""webabcd""30"); 
                        lnk2.NavigateUrl = RouteUrlExpressionBuilder.GetRouteUrl(this, expression); 
                } 
        } 
}
 
 
2、自定义 CacheProvider
CachingEnhancement.aspx
<%-- OutputCache 目前不支持直接设置 providerName 属性 --%> 
<%@ OutputCache Duration="30" VaryByParam="None" %> 

<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true
        CodeBehind="CachingEnhancement.aspx.cs" Inherits="AspDotNet.CachingEnhancement" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
        <%= DateTime.Now.ToString() %> 
</asp:Content>
 
CachingEnhancement.aspx.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

using System.Web.Caching; 
using System.Security.Cryptography; 
using System.Text; 
using System.IO; 
using System.Runtime.Serialization.Formatters.Binary; 

namespace AspDotNet 

        public partial class CachingEnhancement : System.Web.UI.Page 
        { 
void Page_Load() void Page_Load(object sender, EventArgs e) 
                { 
                         
                } 
        } 

        // 重写 OutputCacheProvider 抽象类,以实现自定义的缓存实现(需要重写的方法是 Add, Get, Remove, Set) 
        // 本 Demo 演示了,如何开发一个自定义的 CacheProvider,来实现将数据缓存到硬盘的功能 
        public class FileCacheProvider : OutputCacheProvider 
        { 
                private string _cachePathPrefix = @"c:\"; 

string MD5() string MD5(string s) 
                { 
                        var provider = new MD5CryptoServiceProvider(); 
                        var bytes = Encoding.UTF8.GetBytes(s); 
                        var builder = new StringBuilder(); 

                        bytes = provider.ComputeHash(bytes); 

                        foreach (var b in bytes) 
                                builder.Append(b.ToString("x2").ToLower()); 

                        return builder.ToString(); 
                } 

                /// <summary> 
                /// 将指定的 key ,做md5 加密后,拼出一个路径,做为保存此 key 对应的对象的文件(此例只做演示用) 
                /// </summary> 
                /// <param name="key">缓存 key</param> 
                /// <returns></returns> 
string GetPathFromKey() string GetPathFromKey(string key) 
                { 
                        return _cachePathPrefix + MD5(key) + ".txt"
                } 

                /// <summary> 
                /// 将对象放入自定义的缓存中 
                /// </summary> 
                /// <param name="key">缓存 key</param> 
                /// <param name="entry">缓存对象</param> 
                /// <param name="utcExpiry">缓存的过期时间</param> 
                /// <returns></returns> 
override object Add() override object Add(string key, object entry, DateTime utcExpiry) 
                { 
                        var path = GetPathFromKey(key); 

                        // 指定的 key 已被缓存了,则不做任何处理 
                        if (File.Exists(path)) 
                                return entry; 

                        // 将对象缓存到硬盘上的指定文件 
                        using (var file = File.OpenWrite(path)) 
                        { 
                                var item = new CacheItem { Expires = utcExpiry, Item = entry }; 
                                var formatter = new BinaryFormatter(); 
                                formatter.Serialize(file, item); 
                        } 

                        return entry; 
                } 

                /// <summary> 
                /// 在缓存中,根据指定的 key 获取缓存对象 
                /// </summary> 
                /// <param name="key">缓存 key</param> 
                /// <returns></returns> 
override object Get() override object Get(string key) 
                { 
                        var path = GetPathFromKey(key); 

                        // 未找到缓存 
                        if (!File.Exists(path)) 
                                return null

                        CacheItem item = null

                        // 如果有缓存的话,则取出缓存对象 
                        using (var file = File.OpenRead(path)) 
                        { 
                                var formatter = new BinaryFormatter(); 
                                item = (CacheItem)formatter.Deserialize(file); 
                        } 

                        // 缓存过期或缓存中无数据,则删除此缓存所对应的硬盘上的物理文件 
                        if (item == null || item.Expires <= DateTime.Now.ToUniversalTime()) 
                        { 
                                Remove(key); 
                                return null
                        } 

                        return item.Item; 
                } 

                /// <summary> 
                /// 根据指定的 key 删除缓存对象 
                /// </summary> 
                /// <param name="key">缓存 key</param> 
override void Remove() override void Remove(string key) 
                { 
                        var path = GetPathFromKey(key); 

                        if (File.Exists(path)) 
                                File.Delete(path); 
                } 

                /// <summary> 
                /// 更新缓存 
                /// </summary> 
                /// <param name="key">缓存 key</param> 
                /// <param name="entry">缓存对象</param> 
                /// <param name="utcExpiry">缓存的过期时间</param> 
override void Set() override void Set(string key, object entry, DateTime utcExpiry) 
                { 
                        var item = new CacheItem { Expires = utcExpiry, Item = entry }; 
                        var path = GetPathFromKey(key); 

                        using (var file = File.OpenWrite(path)) 
                        { 
                                var formatter = new BinaryFormatter(); 
                                formatter.Serialize(file, item); 
                        } 
                } 

                /// <summary> 
                /// 封装了需要被缓存的对象的一个可序列化的对象 
                /// </summary> 
                [Serializable] 
                internal class CacheItem 
                { 
                        /// <summary> 
                        /// 缓存对象 
                        /// </summary> 
                        public object Item; 
                         
                        /// <summary> 
                        /// 缓存对象的过期时间 
                        /// </summary> 
                        public DateTime Expires; 
                } 
        } 
}
 
Web.config
<!--缓存配置--> 
<caching> 
        <!--默认的缓存实现是 AspNetInternalProvider(即 asp.net 自带的基于内存的缓存实现方式)--> 
        <outputCache defaultProvider="AspNetInternalProvider"
                <providers> 
                        <!-- 
                                新增一个缓存的 provider 配置 
                                具体实现见 CachingEnhancement.aspx.cs 
                        --> 
                        <add name="FileCache" type="AspDotNet.FileCacheProvider, AspDotNet"/> 
                </providers> 
        </outputCache> 
</caching>
 
Global.asax.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.Security; 
using System.Web.SessionState; 

using System.Web.Routing; 

namespace AspDotNet 

        public class Global : System.Web.HttpApplication 
        { 
                // 根据 HttpContext 的不同,可以为其指定不同的 CacheProvider 
override string GetOutputCacheProviderName() override string GetOutputCacheProviderName(HttpContext context) 
                { 
                        // 符合此条件的,则缓存的实现使用自定义的 FileCacheProvider 
                        // 自定义缓存实现见 CachingEnhancement.aspx.cs 
                        // CacheProvider 的配置见 web.config 
                        // 页面的缓存时间见 CachingEnhancement.aspx 
                        if (context.Request.Path.ToLower().EndsWith("cachingenhancement.aspx")) 
                                return "FileCache"
                        else 
                                return base.GetOutputCacheProviderName(context); 
                } 
        } 
}
 
 
3、表达式 <%: expression %> 的 demo
HtmlEncodedCodeExpressions.aspx
<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true
        CodeBehind="HtmlEncodedCodeExpressions.aspx.cs" Inherits="AspDotNet.HtmlEncodedCodeExpressions" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
         
        <%-- 
                新增的一个表达式 <%: expression %> 相当于 <%= HttpUtility.HtmlEncode(expression) %> 
        --%> 

        <%= "<strong>strong</strong>" %> 
        <br /> 
        <%: "<strong>strong</strong>" %> 
        <br /> 
        <%= HttpUtility.HtmlEncode("<strong>strong</strong>") %> 

</asp:Content>
 
 
4、QueryExtender 控件的 demo
QueryExtenderDemo.aspx
<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true
        CodeBehind="QueryExtenderDemo.aspx.cs" Inherits="AspDotNet.QueryExtenderDemo" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="LinqDataSource1"
                <Columns> 
                        <asp:BoundField DataField="ProductId" HeaderText="ProductId" SortExpression="ProductId" /> 
                        <asp:BoundField DataField="ProductName" HeaderText="ProductName" SortExpression="ProductName" /> 
                        <asp:BoundField DataField="ProductPrice" HeaderText="ProductPrice" SortExpression="ProductPrice" /> 
                </Columns> 
        </asp:GridView> 
        <asp:LinqDataSource ID="LinqDataSource1" runat="server" ContextTypeName="AspDotNet.QueryExtenderDemo" 
                EntityTypeName="AspDotNet.Product" TableName="Data"
        </asp:LinqDataSource> 

        <!-- 
                QueryExtender - 和数据源控件结合使用,以对数据源控件中检索到的数据做再次检索 
                        SearchExpression - 根据指定的字段查找指定的数据 
                        RangeExpression - 在指定字段中查找指定范围的数据 
                        PropertyExpression - 查找某字段的值为某指定的值的数据 
                        OrderByExpression - 用于排序数据 
                        CustomExpression - 自定义查询表达式 
        --> 
        <asp:QueryExtender ID="QueryExtender1" runat="server" TargetControlID="LinqDataSource1"
                <asp:SearchExpression DataFields="ProductName" SearchType="EndsWith"
                        <asp:Parameter Type="String" DefaultValue="0" /> 
                </asp:SearchExpression> 
        </asp:QueryExtender> 
</asp:Content>
 
QueryExtenderDemo.aspx.cs
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

namespace AspDotNet 

        public partial class QueryExtenderDemo : System.Web.UI.Page 
        { 
void Page_Load() void Page_Load(object sender, EventArgs e) 
                { 

                } 

                // 为 GridView 提供数据 
                public List<Product> Data 
                { 
                        get 
                        { 
                                Random random = new Random(); 

                                List<Product> products = new List<Product>(); 
                                for (int i = 0; i < 100; i++) 
                                { 
                                        products.Add(new Product { ProductId = i + 1, ProductName = "名称" + i.ToString().PadLeft(2, '0'), ProductPrice = random.NextDouble() }); 
                                } 

                                return products; 
                        } 
                } 

                // 为 GridView 提供数据的实体类 
                public class Product 
                { 
                        public int ProductId { getset; } 
                        public string ProductName { getset; } 
                        public double ProductPrice { getset; } 
                } 
        } 
}
 
 
5、其他新特性的简单说明
Others.aspx
<%@ Page Title="其它,一笔带过" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" 
        CodeBehind="Others.aspx.cs" Inherits="AspDotNet.Others" %> 

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server"
        <style> 
                body 
                { 
                        font-size: 12px; 
                } 
                textarea 
                { 
                        width: 99%; 
                } 
        </style> 
</asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server"
        <p> 
                1、Permanent Redirect - 可以实现 301 跳转 
                <ul> 
                        <li>Response.RedirectPermanent() - 永久性重定向(http 301)。</li> 
                        <li>Response.Redirect() - 临时性重定向(http 302)。</li> 
                </ul> 
        </p> 
        <p> 
                2、Session 压缩(设置 sessionState 节点的 compressionEnabled 属性) 
                <br /> 
                对于使用进程外会话状态服务器的会话状态提供程序,或者将会话状态保存在 sqlserver 数据库中的会话状态提供程序,现在为提高其效率新增了压缩 Session 数据的功能(使用System.IO.Compression.GZipStream来压缩数据),像如下这样的配置 
                <br /> 
                <textarea rows="6"
                        <sessionState 
                            mode="SqlServer" 
                            sqlConnectionString="data source=dbserver;Initial Catalog=aspnetstate" 
                            allowCustomSqlDatabase="true" 
                            compressionEnabled="true" 
                        /> 
                </textarea> 
        </p> 
        <p> 
                3、httpRuntime 节点的新增配置 
                <ul> 
                        <li>maxRequestPathLength - url 路径的最大长度(基于NTFS文件路径的最大长度就是 260)</li> 
                        <li>maxQueryStringLength - url 的最大长度</li> 
                        <li>requestPathInvalidChars - 指定 url 路径的无效字符</li> 
                        <li>requestValidationType - 继承 System.Web.Util.RequestValidator 抽象类,重写其 IsValidRequestString() 方法,以实现自定义的请求验证。在 requestValidationType 可以指定使用这个自定义的类</li> 
                        <li>encoderType - 重写 System.Web.Util.HttpEncoder,可以实现自定义的 html编码, url编码, http header编码。在 encoderType 指定这个自定义编码的类后,程序中所用到的 System.Web.HttpUtility 或 System.Web.HttpServerUtility 的相关方法将会使用自定义的编码实现</li> 
                </ul> 
                <br /> 
                <textarea rows="2"
                        <httpRuntime maxRequestPathLength="260" maxQueryStringLength="2048" requestPathInvalidChars="<,>,*,%,&,:,\,?" requestValidationType="Samples.MyValidator, Samples" encoderType="Samples.MyEncoder, Samples" /> 
                </textarea> 
        </p> 
        <p> 
                4、compilation 节点新增 targetFramework 属性,用于指定程序运行的目标框架 
                <br /> 
                <textarea> 
                        <compilation targetFramework="4.0" /> 
                </textarea> 
        </p> 
        <p> 
                5、asp.net 4.0 结合 iis 7.5 可使 web 应用程序自动启动 
                <br /> 
                在 web 程序中实现 System.Web.Hosting.IProcessHostPreloadClient 接口,用于被 iis 启动 
        </p> 
        <p> 
                6、Page 类中新增了两个属性,分别是 MetaDescription 和 MetaKeywords 
        </p> 
        <p> 
                7、以前每个可显示的控件都有 Enabled 属性(如果 Enabled="false" 则对应的 HTML 为 disabled="disabled"),但是 HTML 4.01 的标准是只有 input 才能有 disabled 属性 
                <ul> 
                        <li> 
                                在 pages 节点中设置 controlRenderingCompatibilityVersion="3.5",则所有可显示控件都会输出 disabled="disabled" 
                        </li> 
                        <li> 
                                在 pages 节点中设置 controlRenderingCompatibilityVersion="4.0",则只有 input 元素才会输出 disabled="disabled",非 input 元素将会自动标记一个名为 aspnetdisabled 的 css 类 
                        </li> 
                </ul> 
        </p> 
        <p> 
                8、web form 需要在页面上写入隐藏域(如为了保存 ViewState 的隐藏域),在 asp.net 4.0 中系统将在这类的隐藏域外的 div 上标记一个名为 aspNetHidden 的 css 类,以方便样式控制 
        </p> 
        <p> 
                9、ASP.NET Chart Control - 实例参考 http://code.msdn.microsoft.com/mschart 
        </p> 
</asp:Content>
 
 
OK 
[源码下载]

     本文转自webabcd 51CTO博客,原文链接:http://blog.51cto.com/webabcd/341124,如需转载请自行联系原作者


网友评论

登录后评论
0/500
评论
技术小胖子
+ 关注