How to block IP address or IP classes in ASP.NET

Question

I need to block one IP address or class in asp.net

Can anyone help me with the code? And how to implement?

Thanks

Answer 1

You can get the IP address of the client using the HttpRequest.UserHostAddress property (an instance can be accessed using this.Request from any page or using static property HttpContext.Current).

As far as I know, there is no standard method that would compare the IP address with a specified range, so you'll need to implement this bit yourself.

You'll probably want to check this for every request, which can be done either in the OnInit method of every page (that you want to block) or in the BeginRequest event of the application (typically in Global.asax).

If you detect a blocked address, you can output an empty (placeholder) page using Server.Transfer method (Response.End would be another alternative, but that simply cuts the page - returning an empty page, while Server.Transfer allows you to output some message to the client).

Answer 2

If what you mean by "block" is "don't let them harass my server", this is not an asp.net issue, you need a firewall (software or hardware).

If what you mean by "block" is "don't show my pages":

' pseudocode, I haven't checked the exact syntax

Sub Page_Load()
    If HttpRequest.UserHostAddress = "123.123.123.1" then
        Response.Redirect "404.htm" ' send them elsewhere
    end if
End Sub

Answer 3

you mention you are not familiarized with the ASP.NET, so, maybe this excelent article from Rick can help you as it as a full article on how to block IP's and even have an admin area to manage them...

http://www.west-wind.com/WebLog/posts/59731.aspx