如何检查用户输入的命令是否正确- C#

string userInput = "your command here";
string commandPattern = @"^[a-zA-Z]\w+$";
bool isCommandValid = Regex.IsMatch(userInput, commandPattern);

string userInput = "your command here";
string[] commands = { "command1", "command2", "command3" };
bool isCommandValid = commands.Contains(userInput);

string userInput = "your command here";
Dictionary<string, string> commandDictionary = new Dictionary<string, string>
{
    { "command1", "Command 1 description" },
    { "command2", "Command 2 description" },
    { "command3", "Command 3 description" }
};

if (commandDictionary.ContainsKey(userInput))
{
    string commandDescription = commandDictionary[userInput];
    Console.WriteLine("Command exists. Description: " + commandDescription);
}
else
{
    Console.WriteLine("Command does not exist.");
}