public FormBody Add(string key, object value, bool noReplace = false) { if (!noReplace) { StringStringKeyValuePair exists = kvpContainer.Get(key); if (exists != null) { kvpContainer.Remove(exists); } } string stringVal = value is string?Encoding.UTF8.GetString(Encoding.Default.GetBytes((string)value)) : value.ToString(); kvpContainer.Put(new StringStringKeyValuePair(key, stringVal)); return(this); }