C# 身份证号码最后一位计算方法

【实例截图】

【核心代码】

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace 身份证号码最后一位计算方法
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
           
        }

        private void buttonX1_Click(object sender, EventArgs e)
        {
            string sfzmhm_17 = textBoxX1.Text.ToString();
            char[] c = sfzmhm_17.ToCharArray();
            if (sfzmhm_17.Length != 17)
            {
                MessageBox.Show("身份证号码位数不对!");
                return;
            }
            else
            {
            int xx = (int.Parse(c[0].ToString()) * 7)   (int.Parse(c[1].ToString()) * 9)   (int.Parse(c[2].ToString()) * 10)   (int.Parse(c[3].ToString()) * 5)
                  (int.Parse(c[4].ToString()) * 8)   (int.Parse(c[5].ToString()) * 4)   (int.Parse(c[6].ToString()) * 2)   (int.Parse(c[7].ToString()) * 1)
                  (int.Parse(c[8].ToString()) * 6)   (int.Parse(c[9].ToString()) * 3)   (int.Parse(c[10].ToString()) * 7)   (int.Parse(c[11].ToString()) * 9)
                  (int.Parse(c[12].ToString()) * 10)   (int.Parse(c[13].ToString()) * 5)   (int.Parse(c[14].ToString()) * 8)   (int.Parse(c[15].ToString()) * 4)
                  (int.Parse(c[16].ToString()) * 2);
            int ys = xx % 11;
            switch (ys)
            {
                case 0:
                    textBoxX2.Text = "1";
                    break;
                case 1:
                    textBoxX2.Text = "0";
                    break;
                case 2:
                    textBoxX2.Text = "X";
                    break;
                case 3:
                    textBoxX2.Text = "9";
                    break;
                case 4:
                    textBoxX2.Text = "8";
                    break;
                case 5:
                    textBoxX2.Text = "7";
                    break;
                case 6:
                    textBoxX2.Text = "6";
                    break;
                case 7:
                    textBoxX2.Text = "5";
                    break;
                case 8:
                    textBoxX2.Text = "4";
                    break;
                case 9:
                    textBoxX2.Text = "3";
                    break;
                case 10:
                    textBoxX2.Text = "2";
                    break;
            }
            }
        }
    }
}