How can I convert string to integer in golang

Question

I want to convert string to integer in golang. But I don't know the format of string. For example, "10" -> 10, "65.0" -> 65, "xx" -> 0, "11xx" -> 11, "xx11"->0

I do some searching and find strconv.ParseInt(). But it can not handle "65.0". So I have to check string's format.

Is there a better way?

Answer 1

I believe function you are looking for is

strconv.ParseFloat()

see example here

But return type of this function is float64.

If you don't need fractional part of the number passed as the string following function would do the job:

func StrToInt(str string) (int, error) {
    nonFractionalPart := strings.Split(str, ".")
    return strconv.Atoi(nonFractionalPart[0])
}

Answer 2

You can use these three functions to convert a string value to an integer or a float.

Note: the strconv builtin package must be imported to execute these functions.

1. func Atoi(s string) (int, error)
2. func ParseInt(s string, base int, bitSize int) (i int64, err error)
3. func ParseFloat(s string, bitSize int) (float64, error)

package main

import (
    "fmt"
    "strconv"
)

func main() {
    i, _ := strconv.Atoi("-42")
    fmt.Println(i)

    j,_ := strconv.ParseInt("-42", 10, 8)
    fmt.Println(j)

    k,_ := strconv.ParseFloat("-42.8", 8)
    fmt.Println(k)
}