public TerminalMenuItem Show(int?defaultOption = null)
{
bool hasDefault = defaultOption.HasValue && defaultOption.Value > -1;
if (hasDefault)
{
EnsureArgument.InRange(defaultOption.Value, nameof(defaultOption), 0, _items.Count, upperInclusive: false);
}
string title = $"{Title ?? "Select an option"}:";
string promptDefaultTag = hasDefault ? " (enter for default)" : string.Empty;
string prompt = $"option{promptDefaultTag}";
while (true)
{
_terminal.WriteLine(title);
for (var i = 0; i < _items.Count; i++)
{
string itemDefaultTag = i == defaultOption ? " (default)" : string.Empty;
// Use 1-based numbers for the UI
_terminal.WriteLine($" {i + 1}. {_items[i].Name}{itemDefaultTag}");
}
string optionStr = _terminal.Prompt(prompt);
if (string.IsNullOrWhiteSpace(optionStr))
{
if (hasDefault)
{
return(_items[defaultOption.Value]);
}
_terminal.WriteLine("No default option is configured.\n");
continue;
}
if (!int.TryParse(optionStr, out int option))
{
_terminal.WriteLine($"Invalid option '{optionStr}'. Expected a number.\n");
continue;
}
// The option as the user enters it is using a 1-based index
// so we must subtract one to get to the 0-based index we use here.
option--;
if (option < 0 || option >= _items.Count)
{
_terminal.WriteLine($"Invalid option '{optionStr}'.\n");
continue;
}
return(_items[option]);
}
}