How to call function when enter is pressed in text area?

Im trying to send information for a login system with two textfields, when i press login it sends the information perfectly but if I press enter it doesnt work. How can I detect this event with the enter key properly?

Ive got this so far:

#pragma strict

function Start () {
	
}

function Update () {
	if(Input.GetKeyDown("enter")){
		enterPressed = true;
	} else {
		enterPressed = false;
	}
}

var enterPressed : boolean = false;
var Username : String = "";
var Password : String = "";
var loginSuc : boolean = false;
var stringText : String = "";
var loggedinUser : String = "Guest";


function OnGUI () {

	GUI.Label (Rect (380, 380, 100, 750), "Username");
    Username = GUI.TextField (Rect (380, 400, 200, 25), Username, 25);
    
    GUI.Label (Rect (380, 425, 100, 750), "Password");
    Password = GUI.PasswordField(Rect(380,445,200,25), Password,"*"[0],25);  
	
	if (GUI.Button (Rect (445, 480, 70, 25), "Login") || enterPressed == true)
	{
	 	checkPassword();
	 	print ("Button pressed");
	}
	

	GUI.Label (Rect (440, 260, 120, 750), stringText);
	
	GUI.Label (Rect (800, 60, 90, 50), "You are logged in as "+ loggedinUser);
	
}

function checkPassword(){
    //set the WWWForm to send to the PHP page
    var sendLoginInfo : WWWForm = new WWWForm();
       sendLoginInfo.AddField("Username",Username);
       sendLoginInfo.AddField("Password",Password);

    //send the WWWForm via WWW
    var getdata : WWW = new WWW("login.php",sendLoginInfo);
    yield getdata; //Wait for the data to return

    //if TRUE >> Load level    
    if (getdata.text == "true") {
    	login();
    } else {
    	stringText = "Login Failed!";
    }
}

function login(){
	stringText = "Login Successful!";
	loggedinUser = Username;
}

You use a GUI Event in OnGUI which determines whether the current event within the GUI focus is equal to the return keycode. So, in OnGUI (), you would do this:

if (Event.current.keyCode == KeyCode.Return) {
checkPassword();
}

and if you wanted to specify it as a keydown event you would go:

if (Event.current.type == EventType.KeyDown && Event.current.keyCode == KeyCode.Return) {
checkPassword();
}

Hope that helps! Klep

This example should help:

http://forum.unity3d.com/threads/188202-Simple-dynamic-list-editor