C# Address Changing

namespace Gametrainer
{
    public partial class Form1 : Form
    {
        [DllImport("kernel32.dll")]
        public static extern Int32 CloseHandle(IntPtr hObject);
        [DllImport("kernel32.dll")]
        public static extern IntPtr OpenProcess(UInt32 dwDesiredAccess, Int32 bInheritHandle, UInt32 dwProcessId);
        [DllImport("kernel32.dll")]
        public static extern Int32 WriteProcessMemory(IntPtr hProcess, IntPtr lpBaseAddress, uint[] lpBuffer, UInt32 nSize, IntPtr lpNumberOfBytesWritten);


        IntPtr pHandle;   
        Process[] CA;

        public Form1()
        {
            InitializeComponent();
        }

        private void OpenProcess()
        {
            IntPtr pHandle;

            // to write
            IntPtr Address = (IntPtr)0x0000000;
            uint[] Write = new uint[] { 0xFF };// memory to write

            // open
            Process[] CA = Process.GetProcessesByName("Process Name"); 
/*
Ex:
Engine.exe (Combat Arms)
iw4mp.exe (ModernWarfare 2)
warrock.exe (Warrock)
*/

            pHandle = OpenProcess(0xFFFFFF, 0, (UInt32)CA[0].Id);
            WriteProcessMemory(pHandle, Address, Write, 4, (IntPtr)0);
            
            CloseHandle(pHandle);


        }

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

        private void waitfor_Tick(object sender, EventArgs e)
        {
            CA = Process.GetProcessesByName("Engine");
            
            if (CA != null)
            {
                pHandle = OpenProcess(0xFFFFFF, 0, (UInt32)CA[0].Id);
                waitfor.Enabled = false;
                //.....
                button1.Enabled = true;
            }
        }

        private void hackone_Tick(object sender, EventArgs e)
        {
            //16D2A57
            // to write
            IntPtr Address = (IntPtr)0x16D2A57;  //Old addy
            uint[] Write = new uint[] { 0xFF };// memory to write  *New addy*
        }
    }
}