please need to under stand why using to int in this function class MyFunctions { static String convertNumber(String number, String lang) { print("*" * 50); print(number); String res = ""; final arabicsNum = ['٠', '١', '٢', '٣', '٤', '٥', '٦', '٧', '٨', '٩']; if (lang == "ar") { number.split("").forEach((element) { print(element);//String number if (element == ".") { res += "."; } else { res += arabicsNum[int.parse(element).toInt()]; } }); } else { res = number; } return res; }