Item has already been added. Key in dictionary: '.XXX_YYY' Key being added: '.XXX_YYY' RRS feed

  • Question

  • Hi there,

    I would like to ask you a question.

    According to this documentation https://msdn.microsoft.com/en-us/library/system.web.httpresponse.setcookie(v=vs.110).<g class="gr_ gr_35 gr-alert gr_spell gr_inline_cards gr_run_anim ContextualSpelling ins-del multiReplace" data-gr-id="35" id="35">aspx</g>, you suggested that HttpResponse.SetCookie Method (HttpCookie) is not intended to be used directly from your code.
    Could you please explain why? Because we're experiencing a problem with cookie name while we use some code as below:

    var cookieBrowserID = Context.Request.Cookies[CookieName_BrowserID] ?? new HttpCookie(CookieName_BrowserID);
                var cookieVI = Context.Request.Cookies[CookieName_VisitorIdentifier] ?? new HttpCookie(CookieName_VisitorIdentifier);

    This is the stack trace:
    System.ArgumentException: Item has already been added. Key in dictionary: '.XXX_YYY' Key being added: '.XXX_YYY'
    at System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add)
    at System.Collections.Specialized.NameObjectCollectionBase.BaseAdd(String name, Object value)
    at System.Web.HttpRequest.FillInCookiesCollection(HttpCookieCollection cookieCollection, Boolean includeResponse)
    at System.Web.HttpRequest.ResetCookies()

    Could you please give some advice? I really appreciate your help.

    Friday, June 16, 2017 10:20 AM

All replies

  • Hi Gaubeou,

    Thank you for posting here.

    For your question, could you provide more information? 

    I test your code and there is no error for me. HttpResponse.SetCookie method is to update the cookie. When I use add method to add cookie and then use SetCookie method. The value of cookie would be changed. And there is only one XXX_YYY key.

    Could you provide the more information about the error message and code sample for us to reproduce the error?

    Best Regards,


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    Monday, June 19, 2017 9:20 AM