嗨，我有一个日期示例 public static void main(String[] args) {
Observable.just("Alpha", "Beta", "Gamma" ,"Delta",
"Epsilon")
.delay(3000, TimeUnit.SECONDS)
.subscribe(s -> System.out.println("Received: " + s));
sleep(3000);
}
public static void sleep(long millis) {
try {
Thread.sleep(millis);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
的数组，我想将日期转换成所需的格式[2019-02-21T04:06:32.000Z]。所以我正在使用javascript地图
[02/21/2019 4:06:32 AM]在此之后，我控制台了日期数组，但是它仍然显示dateArray.map( x => {
return moment.tz(x, 'Etc/UTC').format('MM/DD/YYYY h:mm:ss A').toString()
});
，但是在map（）内部，它以所需的格式显示。我在这里做错了什么？谁能帮我解决这个问题？谢谢。
答案 0 :(得分：6)
structure(list(Year = structure(c(3L, 3L, 3L, 3L, 3L, 3L, 3L,
3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L), .Names = c("18A01",
"18A02", "18A03", "18A04", "18A05", "18A06", "18A07", "18A08",
"18A09", "18A10", "18A11", "18A12", "18A13", "18A14", "18A15",
"18A16", "18A17", "18A18", "18A19", "18A20"), .Label = c("2001",
"2008", "2018"), class = "factor"), Block = structure(c(1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L), .Names = c("18A01", "18A02", "18A03", "18A04", "18A05",
"18A06", "18A07", "18A08", "18A09", "18A10", "18A11", "18A12",
"18A13", "18A14", "18A15", "18A16", "18A17", "18A18", "18A19",
"18A20"), .Label = c("A", "B", "C", "D", "E", "F", "G", "H",
"I", "J", "X"), class = "factor"), Plot = structure(1:20, .Names = c("18A01",
"18A02", "18A03", "18A04", "18A05", "18A06", "18A07", "18A08",
"18A09", "18A10", "18A11", "18A12", "18A13", "18A14", "18A15",
"18A16", "18A17", "18A18", "18A19", "18A20"), .Label = c(" 1",
" 2", " 3", " 4", " 5", " 6", " 7", " 8", " 9", "10", "11", "12",
"13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23",
"24", "25", "26", "27", "28", "29", "30", "31", "32", "33", "34",
"35", "36", "37", "38", "39", "40", "41", "42", "43", "44", "45",
"46"), class = "factor"), Agrimonia.eupatoria = structure(c(3L,
2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L), .Names = c("18A01", "18A02", "18A03", "18A04", "18A05",
"18A06", "18A07", "18A08", "18A09", "18A10", "18A11", "18A12",
"18A13", "18A14", "18A15", "18A16", "18A17", "18A18", "18A19",
"18A20"), .Label = c("0", "1", "2", "6"), class = "factor"),
Agrostis.capillaris = structure(c(1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Names = c("18A01",
"18A02", "18A03", "18A04", "18A05", "18A06", "18A07", "18A08",
"18A09", "18A10", "18A11", "18A12", "18A13", "18A14", "18A15",
"18A16", "18A17", "18A18", "18A19", "18A20"), .Label = c("0",
"2", "3", "4", "6"), class = "factor"), Agrostis.gigantea = structure(c(1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 3L, 2L, 1L, 3L, 3L,
4L, 3L, 1L, 1L), .Names = c("18A01", "18A02", "18A03", "18A04",
"18A05", "18A06", "18A07", "18A08", "18A09", "18A10", "18A11",
"18A12", "18A13", "18A14", "18A15", "18A16", "18A17", "18A18",
"18A19", "18A20"), .Label = c("0", "2", "3", "4", "6"), class = "factor"),
Agrostis.stolonifera = structure(c(5L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L), .Names = c("18A01",
"18A02", "18A03", "18A04", "18A05", "18A06", "18A07", "18A08",
"18A09", "18A10", "18A11", "18A12", "18A13", "18A14", "18A15",
"18A16", "18A17", "18A18", "18A19", "18A20"), .Label = c("0",
"1", "18", "2", "3", "38", "4", "6", "68", "8"), class = "factor")),
.Names = c("Year",
"Block", "Plot", "Agrimonia.eupatoria", "Agrostis.capillaris",
"Agrostis.gigantea", "Agrostis.stolonifera"), row.names = c("18A01",
"18A02", "18A03", "18A04", "18A05", "18A06", "18A07", "18A08",
"18A09", "18A10", "18A11", "18A12", "18A13", "18A14", "18A15",
"18A16", "18A17", "18A18", "18A19", "18A20"), class = "data.frame")
没有使现有数组发生变异。
您应该这样做：
.map答案 1 :(得分：0)
如果必须更改现有数组，请使用for循环。
dateArray = ['2019-02-21T04:06:32.000Z'];
for(let idx = 0; idx < dateArray.length; idx++){
dateArray[idx] = moment.tz(dateArray[idx], 'Etc/UTC')
.format('MM/DD/YYYY h:mm:ss A').toString();
}