动态切换主题（cookie）

ASP.NET主题切换与Cookie保存

最新推荐文章于 2023-07-13 15:00:15 发布

原创最新推荐文章于 2023-07-13 15:00:15 发布 · 841 阅读

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本文介绍如何在ASP.NET应用程序中实现用户选择的主题切换功能，并通过Cookie保存用户的选择，以便下次访问时能够自动应用所选主题。

在DropDownList选择主题，使用AutoPostBack来自动回送消息，在DropDownList方法中写Cookie的注入和检测。

using System; using System.Collections; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Xml.Linq; public partial class MasterPage : System.Web.UI.MasterPage { protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { string selectedTheme = Page.Theme; HttpCookie preferredTheme = Request.Cookies.Get("PreferredTheme"); if (preferredTheme != null) { selectedTheme = preferredTheme.Value; } if (lstPrefferedTheme.Items.FindByValue(selectedTheme) != null) { lstPrefferedTheme.Items.FindByValue(selectedTheme).Selected = true; } } } protected void lstPrefferedTheme_SelectedIndexChanged(object sender, EventArgs e) { HttpCookie preferredTheme = new HttpCookie("PreferredTheme"); preferredTheme.Expires = DateTime.Now.AddMonths(3); preferredTheme.Value = lstPrefferedTheme.SelectedValue; Response.Cookies.Add(preferredTheme); Response.Redirect(Request.Url.ToString()); } }

然后，在模板中写主题的应用方法。一般写在PreInit里，用 this.PreInit += new EventHandler(Page_PreInit);关联。

using System; using System.Web; /// <summary> ///BasePage 的摘要说明 /// </summary> public class BasePage : System.Web.UI.Page { private void Page_PreRender(object sender, EventArgs e) { if (this.Title == "无标题页") { throw new Exception("Page title cannot be /"Untitle Page/"."); } } public BasePage() { // //TODO: 在此处添加构造函数逻辑 // this.PreRender += new EventHandler(Page_PreRender); this.PreInit += new EventHandler(Page_PreInit); } public void Page_PreInit(object sender, EventArgs e) { HttpCookie preferredTheme = Request.Cookies.Get("PreferredTheme"); if (preferredTheme != null) { Page.Theme = preferredTheme.Value; } } }

如果出现主题的混合出现，将web.config中<pages>的styleSheetTheme的属性删除。