Remove Request QueryString Key Values for Redirection

I wanted to make my page behave in two different modes based on the query string. However it was not strait forward. To make it possible I had to manipulate the URL query string to and remove a key and redirecting it back with a freshly creating URL. Calling Page

bool isKeyFound = false; // Vital to stop calling recursively
string newQueryString = AppHelper.GetNewQueryString (Request.QueryString,"refresh", out isKeyFound);
if (isKeyFound && newQueryString.Length > 0)
{
    Response.Redirect(Request.Path + "?" +newQueryString);
}

Called Method

/// <summary>
/// Recreate a new URL by removing
/// </summary>
/// <param name="queryString">Page Requested string </param>
/// <param name="removeKey">The key to be removed</param>
/// <param name="isKeyFound">This will be a additional info returned</param>
/// <returns></returns>
public static string GetNewQueryString(System.Collections.Specialized.NameValueCollection queryString, string removeKey,out bool isKeyFound)
{
    string returnVal = string.Empty;
    isKeyFound = false ;
    //Build the new query string.
    for (int j = 0; j < queryString.Count; j++)
    {
        // Anything except the target key
        if (!queryString.GetKey(j).ToLower().Equals(removeKey.ToLower()))
        {
            returnVal += queryString.GetKey(j) + "=" + queryString.Get(j) + "&";
        }
        else
        {
            isKeyFound = true;
        }
    }
    //Remove the trailing '&'
    return returnVal.TrimEnd ('&');
}

Happy coding