Cookies

cjo · November 8th, 2003, 01:36 PM

I'm attempting to learn how to use cookies, but I'm getting some inconsistent results. After I instantiate and populate the cookies in the first page with the response object, I'm able to access those cookies from another page with the request object once.

After I close the browser, if I try to open the browser again and go to the page that accesses these cookies, I get an error message that references the line with the first Request.Cookie object and gives the following error message: Object reference not set to an instance of an object.

Here's the first page:

<%@ Page Language="c#" %>
<script language="c#" runat="server">
void SubmitInfo()
{
    HttpCookie ckeName = new HttpCookie("Name");
    ckeName.Value = txtName.Text;
    Response.Cookies.Add(ckeName);

    HttpCookie ckeStreetAddress = new HttpCookie("StreetAddress");
    ckeStreetAddress.Value = txtStreet.Text;
    Response.Cookies.Add(ckeStreetAddress);

    HttpCookie ckeCityStateZip = new HttpCookie("CityStateZip");
    ckeCityStateZip.Value = txtCityStateZip.Text;
    Response.Cookies.Add(ckeCityStateZip);
}
</script>

<html>
<body>
<form id="frmUserInfo" runat="server">
Name: <asp:textbox id="txtName" runat="server" />
<br>
Street Address: <asp:textbox id="txtStreet" runat="server" />
<br>
City, State Zip: <asp:textbox id="txtCityStateZip" runat="server" />
<br>
<br>
<asp:button id="btnSubmit" text="Submit Form" runat="server" onclick="SubmitInfo" />
</form>
</body>
</html>

Here's the second page that's generating the error message, referenced above, on the first line using my Request object:

<%@ Page Language="c#" %>
<script language="c#" runat="server">
void Page_Load(object Source, EventArgs e)
{
    Response.Cache.SetExpires(DateTime.Now);

    Response.Write("You entered the following information: <br><br>");

    Response.Write(Request.Cookies["Name"].Value + "<br>");
    Response.Write(Request.Cookies["StreetAddress"].Value + "<br>");
    Response.Write(Request.Cookies["CityStateZip"].Value + "<br>");
}

</script>

<html>
<body>
</body>
</html>

Can anybody bring me up to speed on what I need to do differently?

Imar · November 8th, 2003, 02:38 PM

Hi there,

By default, cookies expire when you close the browser. That is, a cookie exists only for the duration of a browser session.

To make cookies durable, you need to set the Expires property, like this:

Code:

HttpCookie ckeName = new HttpCookie("Name");
ckeName.Value = txtName.Text;
ckeName.Expires = DateTime.Now.AddDays(10);
Response.Cookies.Add(ckeName);

This makes the cookie last for the next 10 days.

HtH,

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.