79

I am trying to print a string with a uint64 but no combination of strconv methods that I use is working.

log.Println("The amount is: " + strconv.Itoa((charge.Amount)))

Gives me:

cannot use charge.Amount (type uint64) as type int in argument to strconv.Itoa

How can I print this string?

Jonathan Hall
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Anthony
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6 Answers6

118

strconv.Itoa() expects a value of type int, so you have to give it that:

log.Println("The amount is: " + strconv.Itoa(int(charge.Amount)))

But know that this may lose precision if int is 32-bit (while uint64 is 64), also sign-ness is different. strconv.FormatUint() would be better as that expects a value of type uint64:

log.Println("The amount is: " + strconv.FormatUint(charge.Amount, 10))

For more options, see this answer: Golang: format a string without printing?

If your purpose is to just print the value, you don't need to convert it, neither to int nor to string, use one of these:

log.Println("The amount is:", charge.Amount)
log.Printf("The amount is: %d\n", charge.Amount)
Community
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icza
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52

if you want to convert int64 to string, you can use :

strconv.FormatInt(time.Now().Unix(), 10)

or

strconv.FormatUint
Manu
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lingwei64
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11

If you actually want to keep it in a string you can use one of Sprint functions. For instance:

myString := fmt.Sprintf("%v", charge.Amount)
0
func main() {
    var a uint64
    a = 3
    var s string
    s = fmt.Sprint(a)
    fmt.Printf("%s", s)
}
Yongqi Z
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-1

log.Printf

log.Printf("The amount is: %d\n", charge.Amount)
Chris Cherry
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-4

If you came here looking on how to covert string to uint64, this is how its done:

newNumber, err := strconv.ParseUint("100", 10, 64)
Bill Zelenko
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