C# Method to remove end characters or strings

///<summary>
/// Before and after characters (string)
 ///</summary>
///<param name="val">original string</param>
///<param name="str">String to be cut off</param>
///<param name="all">Is it greedy</param>
 ///<returns></returns>
        private string GetString(string val,string str,bool all)
        {
            return (val, @"(^(" + str + ")" + (all ? "*" : "") + "|(" + str + ")"+(all ? "*" : "") + "$)", "");
        }

        /// <summary>
        ///
        /// </summary>
/// <param name="val">original string</param>
/// <param name="c">characts to be intercepted</param>
        /// <returns></returns>
        private string GetString(string val,char c)
        {
            return (c).TrimEnd(c);
        }