Golang strconv.Atoi() is equivalent to ParseInt() function “used to convert string type into int type.” It takes an integer as an argument and returns the string representation of the input value.
Syntax
func Atoi(s string) (int, error)
Arguments
The Atoi() method takes a string as an argument.
Return value
It returns an integer or an error if the value is incompatible with converting it into an integer.
Example 1
To use the Atoi() function in Golang, you must import the strconv package into your program.
In addition, the fmt package is valid when you need to execute I/O operations like printing on the console.
package main
import (
"fmt"
"strconv"
)
func main() {
dataString := "19"
fmt.Printf("%v \n", dataString)
fmt.Printf("%T \n", dataString)
fmt.Println("After using Atoi() Function")
if s, err := strconv.Atoi(dataString); err == nil {
fmt.Printf("%v \n", s)
fmt.Printf("%T \n", s)
}
}
Output
19
string
After using Atoi() Function
19
int
In this example, we imported two packages.
- fmt
- strconv
Inside the main() function, we declare a variable with a string value and print its value and data type.
Using the if statement, we convert a string to an integer using strconv.Atoi() function.
The Atoi() function is equivalent to ParseInt() function, which is also helpful to convert to type int.
Example 2
package main
import (
"fmt"
"strconv"
)
func main() {
fmt.Println(strconv.Atoi("19"))
fmt.Println(strconv.Atoi("-19"))
fmt.Println(strconv.Atoi("212121"))
fmt.Println(strconv.Atoi("-2119"))
fmt.Println(strconv.Atoi("ff"))
fmt.Println(strconv.Atoi("123abc"))
}
Output
19 <nil>
-19 <nil>
212121 <nil>
-2119 <nil>
0 strconv.Atoi: parsing "ff": invalid syntax
0 strconv.Atoi: parsing "123abc": invalid syntax
We took every possible string type in this example and converted it into an integer.
The strconv.Atoi() function also returns an error. The error object will be nil if there is no error.
In this example, if there is no error, nil is returned. Otherwise, an error is returned. For example, while parsing, if it finds a string that can not be converted into an integer, it returns an invalid syntax error.
The Atoi() function is a convenient method for base-10 int parsing.
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Krunal Lathiya is a Software Engineer with over eight years of experience. He has developed a strong foundation in computer science principles and a passion for problem-solving. In addition, Krunal has excellent knowledge of Distributed and cloud computing and is an expert in Go Language.