C#.NET在Web页中设置Cookies
一、设置cookies的方法很简单,有以下两种方法:
1、直接添加Cookie值:
Response.Cookies[“userName”] = “Tom”; Response.Cookies[“userName”].Expires = DateTime.Now.AddDays(1) ; //过期时间,在Cookies文件中无法查看,也不能调用. |
2、创建Cookie对象的一个实例:
HttpCookie cookie=new HttpCookie(“userName”); cookie.Value = “Tom”; cookie.Expires = DateTime.Now.AddDays(1) ; Response.Cookies.Add(aCookie); |
用以上任一方法都可以生成一个有“userName”项的文件, 在你的Internet临时文件夹中你可以查看它。
也可以创建和添加有子键的Cookies,如:
Response.Cookies[“userInfo”][“userName”] = “Tom”; |
或:
HttpCookie cookie=new HttpCookie(“userInfo”); cookie.Values[“userName”] = “Tom”; aCookie.Expires = DateTime.Now.AddDays(1); Response.Cookies.Add(aCookie) |
二、检索Cookies:
Cookies某一键的值为:
Server.HtmlEncode(Request.Cookies[“userInfo”][“userName”])
你可以用Response.Write()方法输出它到页面,如:
Response.Write( Server .HtmlEncode(Request.Cookies[“userInfo”][“userName”])); |
或赋值给其它变量:
string strCookie1=Server.HtmlEncode(Request.Cookies[“userInfo”][“userName”]); |
用Cookies[i]数组可以检索所有项和子键,如:
string[] cooName = new string[Request.Cookies.Count]; string[] cooValue = new string[Request.Cookies.Count]; HttpCookie aCookie; for(int i=0;i<Request.Cookies.Count;i++){ aCookie = Request.Cookies[i]; cooName[i] = Server.HtmlEncode(aCookie.Name); if(!aCookie.HasKeys){ cooValue[i] = Server.HtmlEncode(aCookie.Value); }else{ string[] subcooName = new string[aCookie.Values.Count]; string[] subcooValue = new string[aCookie.Values.Count]; for(int j=0;j<aCookie.Values.Count;j++){ subcooName[j] = Server.HtmlEncode(aCookie.Values.AllKeys[j]); subcooValue[j] = Server.HtmlEncode(aCookie.Values[j]); } } } |
三、修改Cookies
如果是数值类型的Cookie值,比如访问次数,你可以读取该值进行加减操作后再存回,一般的修改直接存入新值就可以了,系统自动用新值覆盖原值,存入的方法与创建相同。
四、删除Cookies
删除Cookies只要把有效期设为失效就可以了,如在创建时设有效期为一天:
cookie.Expires = DateTime.Now.AddDays(1) ; |
要删除则设为:
cookie.Expires = DateTime.Now.AddDays(-1) ; |
删除子键:
HttpCookie cookie; cookie = Request.Cookies[“userInfo”]; aCookie.Values.Remove(“userName”); aCookie.Expires = DateTime.Now.AddDays(1); Response.Cookies.Add(aCookie); |