Question

println("What is the current number of seconds since midnight?")

val s = readInt

val m = (s/60) % 60

val h = (s/60/60) % 24

这是我目前的代码。我只是不知道如何println（“”）所以它以hh：mm形式显示。提前感谢您的帮助！

Answer 1

我认为答案是

"%02d:%02d".format(h, m)

基于http://www.scala-lang.org/old/node/5153

Answer 2

大多数人喜欢@Floris说：

val s = System.currentTimeMillis / 1000
val m = (s/60) % 60
val h = (s/60/60) % 24


val str = "%02d:%02d".format(h, m)
// str = 22:40

现在您可以打印它，就像使用常规字符串一样。

因为scala 2.10有string interpolation feature，所以你可以编写如下内容：

val foo = "bar" 
println(s"I'm $foo!")
// I'm bar!

但我认为它不太可读（提醒perl）：

val str = f"$h%02d:$m%02d"

Answer 3

// show elapsed time as hours:mins:seconds
val t1 = System.currentTimeMillis/1000

// ... run some code
val t2 = System.currentTimeMillis/1000
var elapsed_s = (t2 - t1)

// for testing invent some time: 4 hours: 20 minutes: 10 seconds 
elapsed_s=4*60*60 + 20*60 + 10

val residual_s = elapsed_s % 60
val residual_m = (elapsed_s/60) % 60

val elapsed_h = (elapsed_s/60/60)

// display hours as absolute, minutes & seconds as residuals
println("Elapsed time: " + "%02d:%02d:%02d".format(elapsed_h, residual_m, 
residual_s))

如何在Scala中将秒转换为时间？

3 个答案: