Cookies are used to store user specific information in form of text strings. When a user visits particular website some user specific information gets stored and this information can be retrieved later when the same website gets visited from same machine and can be sent to server. Cookies are associated with websites instead of individual pages.
In ASP.NET cookies can be created using class HttpCookie in System.Web namespace.
Cookies are added to the Cookies collection of response object, the object which is responsible for keeping information to be rendered to browser. Example for writing and reading cookie
Create an instance of HttpCookie
Dim mycookie as new HttpCookie(“userid”)
Set parameters like value and expires
mycookie.Value = “1”
mycookie.Expires = DateTime.Now.AddMonths(1)
Add to the Cookies collection of response object
We can do same thing by directly setting values for Response.Cookies collection
Response.Cookies (“userid”).value = “1”
Response.Cookies (“userid”).Expires = DateTime.Now.AddMonths(1)
The above code creates cookie and store it in user’s drive for one month. The following code is used to retrieve a cookie later.
Request object is used to send cookies information along with the request for page to server.
If Not Requet.Cookies(“userid”) Is Nothing Then
Dim a As String
a= Not Requet.Cookies(“userid”)
Here first we are checking whether cookie exists or not because it can be deleted by user. Cookies won’t work if user has disabled cookies in browser settings.