Read Number from Console Input – Scala
If you are developing a console application with Scala, you may need to read input from the user.
In this tutorial, we will learn how to read a number from the console as input from a user.
To read a number from console input, we use the method scala.io.StdIn.readInt()
, scala.io.StdIn.readFloat()
.
Example 1 – Read Integer from Console as Input
In this example, we shall read an Integer from console. We will increment the value and print it to the console.
example.scala
object ReadInputExample {
def main(args: Array[String]) {
print("Enter a number: ")
var hours = scala.io.StdIn.readInt()
hours = hours + 1
println("Your entry + 1 : "+hours)
}
}
Output
Enter a number: 256
Your entry + 1 : 257
readInt()
method accepts only integers as input. If you provide a float or string, java.lang.NumberFormatException
occurs and the program exits abruptly with exit code 1.
Example 2 – Read Float from Console as Input
In this example, we shall read a float value from console. We will increment the value and print it to the console.
example.scala
object ReadInputExample {
def main(args: Array[String]) {
print("Enter a float value : ")
var length = scala.io.StdIn.readFloat()
length = length + 1
println("Your entry + 1 : "+length)
}
}
Output
Enter a float value : 25.64
Your entry + 1 : 26.64
Using readFloat(), when the console prompts for the input, you provide float, or int or any value of datatype that can be auto typecasted to float.