Alphanumeric auto code generator using web

Default.aspx

 

Default.aspx.cs

 

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Next_Click(object sender, EventArgs e)
    {
        lblvalue1.Text = NxtKeyCode(txtValue.Text);
    }

    public string NxtKeyCode(string KeyCode)
    {
        byte[] ASCIIValues = ASCIIEncoding.ASCII.GetBytes(KeyCode);
        int StringLength = ASCIIValues.Length;
        bool isAllZed = true;
        bool isAllNine = true;
        //Check if all has ZZZ.... then do nothing just return empty string.

        for (int i = 0; i < StringLength - 1; i++)
        {
            if (ASCIIValues[i] != 90)
            {
                isAllZed = false;
                break;
            }
        }
        if (isAllZed && ASCIIValues[StringLength - 1] == 57)
        {
            ASCIIValues[StringLength - 1] = 64;
        }

        // Check if all has 999... then make it A0
        for (int i = 0; i < StringLength; i++)
        {
            if (ASCIIValues[i] != 57)
            {
                isAllNine = false;
                break;
            }
        }
        if (isAllNine)
        {
            ASCIIValues[StringLength - 1] = 47;
            ASCIIValues[0] = 65;
            for (int i = 1; i < StringLength - 1; i++)
            {
                ASCIIValues[i] = 48;
            }
        }

        for (int i = StringLength; i > 0; i--)
        {
            if (i - StringLength == 0)
            {
                ASCIIValues[i - 1] += 1;
            }
            if (ASCIIValues[i - 1] == 58)
            {
                ASCIIValues[i - 1] = 48;
                if (i - 2 == -1)
                {
                    break;
                }
                ASCIIValues[i - 2] += 1;
            }
            else if (ASCIIValues[i - 1] == 91)
            {
                ASCIIValues[i - 1] = 65;
                if (i - 2 == -1)
                {
                    break;
                }
                ASCIIValues[i - 2] += 1;

            }
            else
            {
                break;
            }

        }
        KeyCode = ASCIIEncoding.ASCII.GetString(ASCIIValues);
        return KeyCode;
    }
}

 

Output: