Trying to use StopWatch outside a method

Question

I'm trying to create a stop watch form. I want to be able to have a button I press to get a Lap time just like a normal stop watch. For reasons I don't understand I can't define a Stopwatch variable and call it's constructor in another method. How would I go about making a StopWatch variable so that I can use it in other methods? If I'm not supposed to use a StopWatch what should I be doing?

namespace _Hard0002_StopWatch {
    public partial class StopWatch : Form {
        StateEnum state;
        StopWatch stopWatch;

        public StopWatch() {
            InitializeComponent();
            state = StateEnum.Stoped;
        }

        private void StartButton_Click(object sender, EventArgs e) {
            if (state == StateEnum.Stoped) {
                stopWatch = Stopwatch.StartNew();
                state = StateEnum.Started;
                ChangeFormTittle("Started");
                TimeKeeperText.Text = "0.0";
            }
        }

    private void LapButton_Click(object sender, EventArgs e) {
        //save time elapsed to a string array
        stopWatch.getElapsedTime()//I know this isn't how you call it I just worded it to be readable.
    }

This is the error I'm getting when I try to declare stopWatch in my StartButton_Click()

Cannot implicitly convert type 'System.Diagnostics.Stopwatch' to '_Hard0002_StopWatch.StopWatch'

Answer 1

C#'s stopwatch is Stopwatch. Your class is StopWatch. You declare your variable:

StopWatch stopWatch;

then initialize it:

stopWatch = Stopwatch.StartNew();

using two different objects. Best to rename your form to something like StopwatchForm to prevent from confusing yourself more.