check array for existing element

[buzzykerbox]

Hello again,I'm writing a blackjack game for class,it generates two random numbers that select from a switch statement that creates a string file name of a card e.g "AceDiamonds.gif", it than fills an array deck[] with these strings,I want to fill the array with the full deck of 52 cards,and not have any duplicates, how do I check the array for an existing element remove it and replace with another card not in the deck??
Here is the code,

<script>
var dealer_hand = new Array();
var player_hand = new Array();
var deck = [];
function cardToString(value,suit)
{
var cvalue="";
var csuit="";
switch(value)
	{
	case 1:
	cvalue = "Ace";
	break;
	case 2:
	cvalue = "Two";
	break;
	case 3:
	cvalue = "Three";
	break;
	case 4:
	cvalue = "Four";
	break;
	case 5:
	cvalue = "Five";
	break;
	case 6:
	cvalue = "Six";
	break;
	case 7:
	cvalue = "Seven";
	break;
	case 8:
	cvalue = "Eight";
	break;
	case 9:
	cvalue = "Nine";
	break;
	case 10:
	cvalue = "Ten";
	break;
	case 11:
	cvalue = "Jack";
	break;

	case 12:
	cvalue = "Queen";
	break;
	case 13:
	cvalue = "King";
	break;
	default:
    cvalue=null;
	break;
	}

switch(suit)
	{
	case 1:
	csuit="Clubs";
	break;	
	case 2:
	csuit="Hearts";
	break;	
	case 3:
	csuit="Diamonds";
	break;	
	case 4:
	csuit="Spades";
	break;	
    default:
	csuit=null;
	break;	
	}
if(value==null||suit==null)
  return"";
	
var myCard = cvalue +  csuit +".gif";
 
return myCard;
}//End of cardToString Function


function shuffle()
{
var i=0;
var j=0;

for( i=0;i<52;i++)
	{
	
	var num1 = Math.floor(Math.random()* 13)+1;
    var num2 = Math.floor(Math.random()* 4)+1;
    
    myCard = cardToString(num1,num2);
    
	deck[i]=myCard;
     
        
	}
deck.sort();
for(j=1;j<52;j++)
	{

		while(deck[j] == deck[j-1])
		{
        
		
         var num1 = Math.floor(Math.random()* 13)+1;
         var num2 = Math.floor(Math.random()* 4)+1;
    
         myCard = cardToString(num1,num2);
    
	     deck[j]=myCard;
     
		}

	}
alert(deck);
}
 
</script>
<input type=button value="Shuffle" onclick="shuffle()"/>
</body>

</html>