TypeScript の Tips

 1function formatDate(date: Date, format: string): string {
 2  if (!format) format = "YYYY-MM-DD hh:mm:ss.SSS"
 3
 4  format = format.replace(/YYYY/g, date.getFullYear().toString())
 5  format = format.replace(/MM/g, ("0" + (date.getMonth() + 1)).slice(-2))
 6  format = format.replace(/DD/g, ("0" + date.getDate()).slice(-2))
 7  format = format.replace(/hh/g, ("0" + date.getHours()).slice(-2))
 8  format = format.replace(/mm/g, ("0" + date.getMinutes()).slice(-2))
 9  format = format.replace(/ss/g, ("0" + date.getSeconds()).slice(-2))
10  if (format.match(/S/g)) {
11    var milliSeconds = ("00" + date.getMilliseconds()).slice(-3)
12    var length = format.match(/S/g).length
13    for (var i = 0; i < length; i++)
14      format = format.replace(/S/, milliSeconds.substring(i, i + 1))
15  }
16  return format
17}

1const unixTimeZero = Date.parse('01 Jan 1970 00:00:00 GMT');
2const unixTimeZeroDate = new Date(unixTimeZero);
3const javaScriptRelease = Date.parse('04 Dec 1995 00:12:00 GMT');

 1let time = Date.parse("2001");
 2let date = new Date(time);
 3console.log(date.toISOString());  // 出力：2001-01-01T00:00:00.000Z
 4
 5time = Date.parse("2001-02");
 6date = new Date(time);
 7console.log(date.toISOString());  // 出力：2001-02-01T00:00:00.000Z
 8
 9time = Date.parse("2001-02-03");
10date = new Date(time);
11console.log(date.toISOString());  // 出力：2001-02-03T00:00:00.000Z
12
13time = Date.parse("2001-02-03T04:05");
14date = new Date(time);
15console.log(date.toISOString());  // 出力：2001-02-02T19:05:00.000Z
16time = Date.parse("2001-02-03T04:05+09:00");
17date = new Date(time);
18console.log(date.toISOString());  // 出力：2001-02-02T19:05:00.000Z
19time = Date.parse("2001-02-03T04:05Z");
20date = new Date(time);
21console.log(date.toISOString());  // 出力：2001-02-03T04:05:00.000Z
22
23time = Date.parse("2001-02-03T04:05:06");
24date = new Date(time);
25console.log(date.toISOString());  // 出力：2001-02-02T19:05:06.000Z
26time = Date.parse("2001-02-03T04:05:06+09:00");
27date = new Date(time);
28console.log(date.toISOString());  // 出力：2001-02-02T19:05:06.000Z
29time = Date.parse("2001-02-03T04:05:06Z");
30date = new Date(time);
31console.log(date.toISOString());  // 出力：2001-02-03T04:05:06.000Z
32
33time = Date.parse("2001-02-03T04:05:06.078");
34date = new Date(time);
35console.log(date.toISOString());  // 出力：2001-02-02T19:05:06.078Z
36time = Date.parse("2001-02-03T04:05:06.078+09:00");
37date = new Date(time);
38console.log(date.toISOString());  // 出力：2001-02-02T19:05:06.078Z
39time = Date.parse("2001-02-03T04:05:06.078Z");
40date = new Date(time);
41console.log(date.toISOString());  // 出力：2001-02-03T04:05:06.078Z
42
43time = Date.parse("+123456-07-08T09:10:11.012");
44date = new Date(time);
45console.log(date.toISOString());  // 出力：+123456-07-08T00:10:11.012Z
46time = Date.parse("+123456-07-08T09:10:11.012+09:00");
47date = new Date(time);
48console.log(date.toISOString());  // 出力：+123456-07-08T00:10:11.012Z
49time = Date.parse("+123456-07-08T09:10:11.012Z");
50date = new Date(time);
51console.log(date.toISOString());  // 出力：+123456-07-08T09:10:11.012Z
52
53time = Date.parse("");
54console.log(time);  // 出力：NaN