asp.net – How2：在HttpModule中挂钩的事件,用于将js链接放入head元素

我想让HttpModule从一些简单的配置数据中注入javascripts,css链接到HEAD元素.我不确定应该挂哪个事件？

我可以使用
– context.PreRequestHandlerExecute用于动态更改母版页
– 用于SEO优化的Context.BeginRequest

在HTTPModule Event Execution Order?有一些帮助

谢谢你的提示.干杯,X.

解决方法

这是我在没有HttpModule的情况下实现你正在做的事情的方法.我不喜欢httpmodule的想法,因为如果我忘记注册它并且它没有运行,我的应用程序将无法工作,这将是一个非常明显的错误.该页面绝对需要包含JS,因此我决定将其放在项目的基本Page类中.

我在几年前实现了,并希望能够包含更多脚本,它支持css,元标记等….我忘了为什么我使用Page.Header.Controls.Add而不仅仅是Page.ClientScript.RegisterClientscriptinclude但是有一个原因.

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;

namespace YourNamespace
{
    public class HeaderIncludesManager
    {
        private List<string> m_IncludedFiles = new List<string>();

        public void IncludeScript(string s)
        {
            IncludeScript(s,null);
        }

        public bool IsIncluded(string file)
        {
            return (m_IncludedFiles.Find(s => s.Equals(file,StringComparison.InvariantCultureIgnoreCase)) != null);
        }

        public void IncludeScript(string script,string condition)
        {
            Page page = HttpContext.Current.CurrentHandler as Page;
            if (!IsIncluded(script) || page == null)
                return;

            string scriptFile = string.Format("/{0}/{1}?v={2}",MyConfig.JSDir,script,MyConfig.BuildNumber);
            if (page.Header != null)
            {
                string scriptTag = String.Format("<script language=\"javascript\" type=\"text/javascript\" src=\"{0}\"></script>\n",scriptFile);
                if (!String.IsNullOrEmpty(condition))
                    scriptTag = String.Format("<!--[{0}]><script language=\"javascript\" type=\"text/javascript\" src=\"{1}\"></script><![endif]-->\n",condition,scriptFile);

                page.Header.Controls.Add(new LiteralControl(scriptTag));
                m_IncludedFiles.Add(script);
            }
            else if (!page.ClientScript.IsClientscriptincludeRegistered(GetType(),scriptFile))
            {
                page.ClientScript.RegisterClientscriptinclude(GetType(),scriptFile,scriptFile);
                m_IncludedFiles.Add(script);
            }
        }

        public void IncludeCss(string css)
        {
            Page page = HttpContext.Current.CurrentHandler as Page;
            if (!IsIncluded(css) || page == null)
                return;

            string cssfile = string.Format("/{0}/{1}?v={2}",MyConfig.CssDir,css,MyConfig.BuildNumber);
            if (page.Header != null)
            {
                ((Page)HttpContext.Current.CurrentHandler).Header.Controls.Add(new LiteralControl(String.Format("<link href=\"{0}\" rel=\"stylesheet\" type=\"text/css\" />\n",cssfile)));                    
                m_IncludedFiles.Add(css);
            }
        }

        public void IncludeJQuery()
        {
            IncludeScript("jquery-1.2.3.min.js");
        }

        public void IncludeJQueryUI()
        {
            IncludeJQuery();
            IncludeScript("jquery.ui.1.0.min.js");
            IncludeCss("jquery-theme.css");
        }

        public void IncludeFlotScripts()
        {
            IncludeJQuery();
            IncludeScript("flot/jquery.flot.js");
            IncludeScript("flot/excanvas.pack.js","if IE");
        }
    }

    public class MyPage : Page
    {
        public HeaderIncludesManager HeaderIncludes = new HeaderIncludesManager();
    }

    public class MyControl : UserControl
    {
        public new MyPage Page
        {
            get
            {
                return (MyPage)base.Page;
            }
        }
    }

    public class SomeControlThatNeedsScripts : MyControl
    {
        protected override void OnLoad(EventArgs e)
        {
            Page.HeaderIncludes.IncludeJQueryUI();
            base.OnLoad(e);
        }
    }
}