电话号码格式 function 如何写

    public string formatPhoneNumber(string phoneNumber)
        {

            var piece1 = phoneNumber.substring(0, 3); //123
            var piece2 = phoneNumber.substring(3, 6); //456
            var piece3 = phoneNumber.substring(6); //7890

            //should return (123)456-7890
            return String.Format("({0})-{1}-{2}", piece1, piece2, piece3);
        }

error 有 cannot resolve for symbol substring,

大牛们有没有办法帮忙？ --------------------编程问答-------------------- http://topic.csdn.net/t/20040609/13/3076793.html --------------------编程问答-------------------- 用一个正则表达式就直接做了
private static Regex RegPhone = new Regex("^[0-9]+[-]?[0-9]+[-]?[0-9]$"); --------------------编程问答-------------------- 你这样子截取也不对呀 --------------------编程问答-------------------- var piece2 = phoneNumber.substring(3, 3); //456
return String.Format("({0}){1}-{2}", piece1, piece2, piece3); --------------------编程问答--------------------

引用 4 楼的回复:

var piece2 = phoneNumber.substring(3, 3); //456
return String.Format("({0}){1}-{2}", piece1, piece2, piece3);

楼上正解,楼主误解了
substring(3, 3); //从3开如,取3位 --------------------编程问答-------------------- 加个命名空间using System.Text.RegularExpressions;
//验证手机,这是一个验证1开头的,11位数字组成的号码,现在号码变化快,还是不要限定死了
        Label5.Text = "";
        Regex rx = new Regex(@"^1\d{10}$");
        if (Text3.Value == string.Empty)
        {
            Label5.Visible = true;
            Label5.Text = "手机不能为空.";
        }
        else if (!rx.IsMatch(Text3.Value))
        {
            Label5.Visible = true;
            Label5.Text = " 请输入正确手机号码.";
        }

补充：.NET技术 ,  ASP.NET