在Scala中格式化長和雙println

Question

爲了格式化Long或Double類型變量，'％'後面應該用什麼後綴？

var LONG : Long = 9L; 
println("The value of LONG is %?".format(LONG)); 
var DOUBLE : Double = 9.9; 
println("The value of DOUBLE is %?".format(DOUBLE)); 

非常感謝。

Answer 1

這裏是你如何在println發言中，我們可以使用的String.format（）方法的格式，格式如下圖所示

var LONG : Long = 9L; 
println("The value of LONG is %d\n".format(LONG)) 
var DOUBLE : Double = 9.9; 
printf("The value of DOUBLE is %.2f".format(DOUBLE)); 

結果你： -

LONG的值是9

DOUBLE的值是9.90

更多選項格式化標誌是指http://web.cerritos.edu/jwilson/SitePages/java_language_resources/Java_printf_method_quick_reference.pdf

Answer 2

In Scala we write

val height = 1.9d 
val weight = 100L 
val name = "James" 
println(f"$name%s is $height%2.2f meters tall and weights $weight%3d kg") // James is 1.90 meters and weights 100 kg