How to determine whether it is a number in golang

When using Golang for development, it is often necessary to judge the type of data. Among them, determining whether the data is numeric is also a common requirement. This article will introduce how to determine whether the data is a number in Golang.

Method 1: Use the strconv package

The strconv package is a package in Golang used to convert strings into basic types. You can use it to determine whether a string is a number. The specific operation is as follows:

import "strconv"

func IsNumber(str string) bool {
    _, err := strconv.Atoi(str)
    return err == nil
}

In this function, the Atoi function will try to convert the string into an integer type. If an error occurs, an error object will be returned. We only need to check whether it is nil, that is Can. Returns true if it is a number, false otherwise.

It should be noted that this function can only judge integers. If you need to judge floating point numbers, you need to use the ParseFloat function.

Method 2: Use regular expressions

Regular expressions are a method of matching strings from text, and can also be used to determine whether a string is a number. Golang has built-in regular expression support, which can be implemented using the functions in the regexp package. The specific implementation is as follows:

import "regexp"

func IsNumber(str string) bool {
    pattern := "^[0-9]+$"
    match, err := regexp.MatchString(pattern, str)
    if err != nil {
        return false
    }
    return match
}

In this function, we use the regular expression ^[0-9] $ to match pure numeric strings. MatchString The function returns a Boolean value and an error object at the same time. If the match is successful, it returns true, otherwise it returns false. It should be noted that if there is a problem with the regular expression itself, an error will be returned.

Method 3: Use Unicode

In Golang, each character has its corresponding Unicode code point, where the code point range of numeric characters is U 0030 to U 0039. So we can tell if it's a number by looping through the string and looking at the Unicode code point of each character. The implementation is as follows:

func IsNumber(str string) bool {
    for _, char := range str {
        if char  '9' {
            return false
        }
    }
    return true
}

In this function, we iterate through each character in the string and check whether its Unicode code point is within the range of numeric characters. Returns false if any character is not a digit; returns true if all are digits.

To sum up, the above three methods can be used to determine whether a string is a number. Methods 1 and 3 are simpler, faster and have wider applicability.

The above is the detailed content of How to determine whether it is a number in golang. For more information, please follow other related articles on the PHP Chinese website!