1switch (new Date().getDay()) {
2  case 0:
3    day = "Sunday";
4    break;
5  case 1:
6    day = "Monday";
7    break;
8  case 2:
9    day = "Tuesday";
10    break;
11  case 3:
12    day = "Wednesday";
13    break;
14  case 4:
15    day = "Thursday";
16    break;
17  case 5:
18    day = "Friday";
19    break;
20  case 6:
21    day = "Saturday";
22}
23

1var d = new Date();
2var n = d.toLocaleString("en-US", { "weekday": "long" }); // Monday
3n += "\n" + d.toLocaleString("en-US", { "weekday": "short" }); // Mon
4n += "\n" + d.toLocaleString("en-US", { "weekday": "narrow" }); // M

1var d = new Date();
2var n = d.getDay();