ParseInt（）中使用的基本参数是什么？

Question

I have come across many sample code whenever we try to convert string to int we use :

parseValue, err := strconv.ParseInt(value, 10, 64)

So the code above ParseInt() has three arguments. from the documentation code :

func ParseInt(s string, base int, bitSize int) (i int64, err error) {

I tried to understand the base inthere so I change the value from 0 to 16. PlayGolang.

The result is ok when the input are 0 and 10. Number other that 0 and 10 are panic. I still confused and not understand. Can someone explain what base is used for in ParseInt()?

Answer 1

You are converting a string to an integer. The method is asking you for the base (number system) the string is in. You can learn more about number systems here: https://en.wikipedia.org/wiki/Radix

For example (using your code snippet provided here):

var s string = "1111" // This string is in binary (Base 2)
i, err := strconv.ParseInt(s, 2, 64) // Give the base as 2

Result:

Hello, 15 with type int64!