怎样用Golang生成随机密码 实现可定制的密码生成器

package main

import (
    "crypto/rand"
    "fmt"
    "math/big"
)

// GenerateRandomPassword generates a random password of a specified length using a given character set.
func GenerateRandomPassword(length int, charSet string) (string, error) {
    result := make([]byte, length)
    for i := 0; i < length; i++ {
        num, err := rand.Int(rand.Reader, big.NewInt(int64(len(charSet))))
        if err != nil {
            return "", err
        }
        result[i] = charSet[num.Int64()]
    }
    return string(result), nil
}

func main() {
    // Define the character set for the password.
    charSet := "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()"

    // Specify the desired password length.
    passwordLength := 16

    // Generate the random password.
    password, err := GenerateRandomPassword(passwordLength, charSet)
    if err != nil {
        fmt.Println("Error generating password:", err)
        return
    }

    // Print the generated password.
    fmt.Println("Generated Password:", password)
}

import (
    "regexp"
)

// ValidatePassword checks if a password meets certain criteria.
func ValidatePassword(password string) bool {
    hasNumber := regexp.MustCompile(`[0-9]`).MatchString(password)
    hasSpecialChar := regexp.MustCompile(`[!@#$%^&*()]`).MatchString(password)
    return hasNumber && hasSpecialChar
}


// GeneratePasswordWithValidation generates a password that meets specific criteria.
func GeneratePasswordWithValidation(length int, charSet string) (string, error) {
    for i := 0; i < 100; i++ { // 尝试最多100次
        password, err := GenerateRandomPassword(length, charSet)
        if err != nil {
            return "", err
        }
        if ValidatePassword(password) {
            return password, nil
        }
    }
    return "", fmt.Errorf("failed to generate a valid password after multiple attempts")
}