WLC_Programming Knowledge

 eg. Hex = 1AD, Binary =? 
          so, Hex  = 1        A      D   
                       = 0001 1010 1101   
                       = 000110101101<2> 
Hex(1AD) = Binary(000110101101)

using System;
using System.Windows.Forms;

namespace Converter
{
    public partial class HexToBinary : Form
    {
        public HexToBinary()
        {
            InitializeComponent();
        }

        public string HexadecimalToBinary(string hex)
        {
            string Bi = "";
            string Binary = "";
            int i = 0;
            char[] HexArr = hex.ToCharArray();
            while (HexArr.Length > i)
            {
                switch (HexArr[i])
                {
                    case '0': Bi = "0000"; break;
                    case '1': Bi = "0001"; break;
                    case '2': Bi = "0010"; break;
                    case '3': Bi = "0011"; break;
                    case '4': Bi = "0100"; break;
                    case '5': Bi = "0101"; break;
                    case '6': Bi = "0110"; break;
                    case '7': Bi = "0111"; break;
                    case '8': Bi = "1000"; break;
                    case '9': Bi = "1001"; break;
                    case 'A': Bi = "1010"; break;
                    case 'B': Bi = "1011"; break;
                    case 'C': Bi = "1100"; break;
                    case 'D': Bi = "1101"; break;
                    case 'E': Bi = "1110"; break;
                    case 'F': Bi = "1111"; break;
                    default: Bi = ""; break;
                }
                Binary += Bi +" ";
                i++;
            }
            return Binary;
        }

        private void btnConvert_Click(object sender, EventArgs e)
        {
            txtBinary.Text = HexadecimalToBinary(txtHexadecimal.Text.ToUpper()).ToString();       
        }

        private void btnReset_Click(object sender, EventArgs e)
        {
            txtHexadecimal.Clear();
            txtBinary.Clear();
            txtHexadecimal.Focus();
        }
    }
}

Hex = 1AD, Binary=? 
char[] HexArr = { '1', 'A', 'D'};   
i = 0; 
Loop1 => while(HexArr.Length >0) =>    
               while(3 > 0) => true   
                    switch(HexArr[i]) => 
                    switch(HexArr[0]) => case '1': Bi = "0001"; break;  
                         so, Bi = 0001   
                         i++;   

i = 1; 
Loop2 => while(3 > 1) => true   
                     switch(HexArr[1]) => case 'A': Bi = "1010"; break;  
                          so, Bi = 1010   
                          i++;   

i = 2; 
Loop3 => while(3 > 2) => true   
             switch(HexArr[2]) => case 'D': Bi = "1101"; break;  
         so, Bi = 1101   
         i++;   

i = 3; 
Loop4 => while(3 > 3) => false 
so, Binary = Loop1 Loop2 Loop3 = 0001 1010 1101