ASP. NET Cookie

A cookie is a piece of text information in which the client store Cookie is one of the methods that the session state of ASP. NET will request to associate with session. Cookies can also be used directly to persist data between requests, but the data is then stored on the client and sent to the server along with each request. The browser has a limit on the size of the Cookie, so only4096byte is guaranteed to be accepted. Writing Cookies//Mode 1:response.cookies["username"].value="Mike"; response.cookies["username"]. expires=DateTime.MaxValue;//Mode 2:HttpCookie Acookie =NewHttpCookie (" Last"); Acookie. Value="a"; Acookie. Expires=DateTime.MaxValue; RESPONSE.COOKIES.ADD (acookie);//the notation of multi-valued cookies//Mode 1:response.cookies["Userinfo1"]["name"].value="Mike"; response.cookies["Userinfo1"][" Last"].value="a"; response.cookies["Userinfo1"]. expires=DateTime.MaxValue;//Mode 2:HttpCookie cookie =NewHttpCookie ("Userinfo1"); cookies. values["name"]="Mike"; a cookie. values[" Last"]="a"; a cookie. Expires=DateTime.MaxValue;//cookies. Expires = System.DateTime.Now.AddDays (1);//set Expiration time 1 daysResponse.Cookies.Add (cookies); Read Cookies Internet Explorer saves the site's cookie in the file name format as<user>@<domain>.txt file, where <user>is the name of your account. Note: Before you obtain the value of a cookie, you should ensure that the cookie does exist. Otherwise, you will get an exception if (request.cookies["UserName"]!=NULL){  stringstr = Request.Cookies ("UserName"). Value; }//read a multi-valued cookieIf (request.cookies["UserInfo1"]!=NULL ){  stringname=request.cookies["UserInfo1"]["name"]; stringlast=request.cookies["UserInfo1"][" Last"]; }//Read the Cookie collection for(inti =0; i<request.cookies.count; i++.) {HttpCookie cookies=Request.Cookies; Response.Write ("name="+cookies. mame+"<br/>"); if(cookies.) HasKeys)//whether there are children keys{System.Collections.Specialized.NameValueCollection Namecoll =acookie.values;  for(intj=0; j<namecoll.count;j++) {Response.Write ("sub-Key name ="+ Namecoll.allkey[j] +"<br/>"); Response.Write ("sub-key value ="+ Namecoll[j] +"<br/>"); }    }    Else{Response.Write ("value="+cookies. Value+"<br/>"); When you run this code, you see a cookie,asp named "Asp.net_sessionid". NET uses this Cookie to hold a unique identifier for your session. Modify cookie Modify method same as Create method delete the cookie to set its validity period to a date in the past. This expired cookie is deleted when the browser checks the validity period of the cookie. HttpCookie Cookies=NewHttpCookie ("Userinfo1"); cookies. Expires=datetime.now.adddays (- -); RESPONSE.COOKIES.ADD (cookies); Modify Cookies1response.cookies["Info"]["User"] ="2";2response.cookies["Info"]. Expires = DateTime.Now.AddDays (1); Delete a property under a cookie1HttpCookie acookie=request.cookies["Info"];2Acookie. Values.remove ("userid");3Acookie. Expires = DateTime.Now.AddDays (1);4Response.Cookies.Add (Acookie); Delete all cookies, that is, set the expiration time for now.1 intLimit=request.cookies.count-1;2  for(intI=0; i<limit;i++)3 {4Acookie =request.cookies (i)5Acookie. Expires = DateTime.Now.AddDays (-1)6Response.Cookies.Add (Acookie)7 }     -------------If you have a master station and a level two domain name station and the cookie is shared, add the following settings cookie. Domain=". Primary Domain"; a cookie. Path="/";