if condition in foreach loop

[CGKevin]

Assuming you actually wanted to replace the if construct (instead of the foreach as stated in your reply to TGC - foreach is the best way to iterate through a List)...

    foreach (var name in Students) {
        switch (name.StudentName.ToLower()) {
            case "john":
                // Do something specific to John
                break;
            case "alex":
                // Do something specific to Alex
                break;
            case "james":
            case "robert":
                // Do something specific to both James and Robert
                break;
            default:
                // Do something if not John, Alex, James, or Robert
                break;
        }
        // If you need - you can do something here common to all
    }