Beyond_Beyaan.BBSingleLineTextBox.ReplaceSelectedText C# (CSharp) Метод

        public void ReplaceSelectedText(string replacement)
        {
            if (Text.Length == SelectedText.Length)
            {
                SelectedText = string.Empty;
                SetText(replacement);
                return;
            }

            string beforeSelected = Text.Substring(0, SelectedTextIndex);
            int selectedTextIndexOfLast = SelectedTextIndex + (SelectedText.Length - 1);
            string afterSelected = Text.Substring(selectedTextIndexOfLast + 1, Text.Length - 1 - selectedTextIndexOfLast);
            SelectedText = string.Empty;
            SetText(beforeSelected + replacement + afterSelected);
        }