RemoveVietNamSign.cs

using System;
using System.Collections.Generic;
using System.Text;

namespace Sieve.Models
{
    public class RemoveVietNamSign
    {
        private string[] VietnameseSigns = new string[]
           {

            "aAeEoOuUiIdDyY",

            "áàạảãâấầậẩẫăắằặẳẵ",

            "ÁÀẠẢÃÂẤẦẬẨẪĂẮẰẶẲẴ",

            "éèẹẻẽêếềệểễ",

            "ÉÈẸẺẼÊẾỀỆỂỄ",

            "óòọỏõôốồộổỗơớờợởỡ",

            "ÓÒỌỎÕÔỐỒỘỔỖƠỚỜỢỞỠ",

            "úùụủũưứừựửữ",

            "ÚÙỤỦŨƯỨỪỰỬỮ",

            "íìịỉĩ",

            "ÍÌỊỈĨ",

            "đ",

            "Đ",

            "ýỳỵỷỹ",

            "ÝỲỴỶỸ"
           };
        public string RemoveSignAndUpperVietnameseString(string str)
        {
            if (str==null)
            {
                return "";
            }
            for (int i = 1; i < VietnameseSigns.Length; i++)
            {
                for (int j = 0; j < VietnameseSigns[i].Length; j++)
                    str = str.Replace(VietnameseSigns[i][j], VietnameseSigns[0][i - 1]);
            }
            return str.ToUpper();
        }
    }
}