Question

I need to check that our visitors are using HTTPS. In BasePage I check if the request is coming via HTTPS. If it’s not, I redirect back with HTTPS. However, when someone comes to the site and this function is used, I get the error:

System.Web.HttpException: Server
cannot append header after HTTP
headers have been sent. at
System.Web.HttpResponse.AppendHeader(String
name, String value) at
System.Web.HttpResponse.AddHeader(String
name, String value) at
Premier.Payment.Website.Generic.BasePage..ctor()

Here is the code I started with:

// If page not currently SSL
if (HttpContext.Current.Request.ServerVariables["HTTPS"].Equals("off"))
{
    // If SSL is required
    if (GetConfigSetting("SSLRequired").ToUpper().Equals("TRUE"))
    {
        string redi = "https://" +
        HttpContext.Current.Request.ServerVariables["SERVER_NAME"].ToString() +
        HttpContext.Current.Request.ServerVariables["SCRIPT_NAME"].ToString() +
        "?" + HttpContext.Current.Request.ServerVariables["QUERY_STRING"].ToString();
        HttpContext.Current.Response.Redirect(redi.ToString());
    }
}

I also tried adding this above it (a bit I used in another site for a similar problem):

// Wait until page is copletely loaded before sending anything since we re-build
HttpContext.Current.Response.BufferOutput = true;

I am using c# in .NET 3.5 on IIS 6.

Answer 1

Chad,
Did you try ending the output when you redirect? There is a second parameter that you’d set to true to tell the output to stop when the redirect header is issued. Or, if you are buffering the output then maybe you need to clear the buffer before doing the redirect so the headers are not sent out along with the redirect header.

Brian