var _TabsArray = new Array();
_TabsArray[0] = "Tab1";
_TabsArray[1] = "Tab2";
_TabsArray[2] = "Tab3";

function Mostrar(TabName)
{
    for (i = 0; i < _TabsArray.length; i++)
    {
        if (_TabsArray[i] != TabName)
            document.getElementById(_TabsArray[i]).style.display = "none";
    }
    document.getElementById(TabName).style.display = "";
}