you could also use the LINQ version of it,
Code:
var pairs = UserCollection.Select(u => { return Tuple.Create(u.Username, u.Password); });
foreach (var pair in pairs)
{
listBox1.Add(pair.Item1);
listBox2.Add(pair.Item2);
}
or, if you love the SQL syntax:
Code:
var query = from user in UserCollection select new { Name = user.Username, Password = user.Password };
// anonymous type
foreach (var userData in query) {
listBox1.Add(userData.Name);
listBox2.Add(userData.Password);
}