How to convert a string to a number in Golang?

In Go language, you can use functions in the strconv package to convert strings to numbers. The specific implementation steps are as follows:

1. import the strconv package: import “strconv”
2. Convert using functions in the strconv package.
3. Convert a string to an integer using the Atoi function: num, err := strconv.Atoi(str)
4. Convert the string to an int64 type using the ParseInt function: num, err := strconv.ParseInt(str, 10, 64)
5. Use the ParseFloat function to convert a string to a float64 type: num, err := strconv.ParseFloat(str, 64)
6. Handle the conversion results and errors as necessary.
7. The conversion was successful, the num variable holds the converted number, and the err variable is nil.
8. The conversion failed, the num variable is now 0, and the error variable holds the error message. You can print the error message using fmt.Println(err).

Here is a complete example code:

package main

import (
	"fmt"
	"strconv"
)

func main() {
	str := "12345"

	// 字符串转换为int类型
	num, err := strconv.Atoi(str)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(num)
	}

	// 字符串转换为int64类型
	num64, err := strconv.ParseInt(str, 10, 64)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(num64)
	}

	// 字符串转换为float64类型
	fnum, err := strconv.ParseFloat(str, 64)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(fnum)
	}
}

The output is:

12345
12345
12345

This achieves the function of converting a string into a number.