Question

我正在尝试制作一个密码验证程序，用于测试以下条件：

The password should be at least 8 characters long
The password should contain at least one uppercase and at least one lowercase
The password should have at least one digit
The password should 1 special character: ! @ # $ % & * : ;

我让程序在没有函数的情况下工作，所以我尝试创建一个测试每个条件的函数，但由于某种原因，strlen在我的函数中不起作用。我包括cstring和cctype但我无法弄清楚为什么错误仍然存在。请帮忙！

#include <iostream>
#include <cctype>
#include <cstring>
using namespace std;

void criteraValidation(string str1, int up, int low, int digit, int special);

int main()
{
    const int SIZE = 20;
    char password[SIZE];
    int Upper, Lower, Digit, SpecialChar;

    cout << "Password Validation Criteria" << endl;
    cout << "The password should be at least 8 characters long" << endl;
    cout << "The password should contain at least one uppercase and at least one lowercase letter" << endl;
    cout << "The password should have at least one digit" << endl;
    cout << "The password should 1 special character: ! @ # $ % & * : ; " << endl;

    do
    {
        Upper = Lower = Digit = SpecialChar = 0;

        cout << "Enter password: ";
        cin.getline(password, SIZE);

    }
    while (SpecialChar == 0 || Upper == 0 || Lower == 0 || Digit == 0 || strlen(password) < 8);

    cout << "All crieria have been met! Password: " << password << endl;

    return 0;
}

    void criteraValidation(string str1, int up, int low, int digit, int special)
    {

        for (int i = 0; i < strlen(str1); i++)
        {
            if (isupper(str1[i])) // checks uppercase letters
                up++;
            if (islower(str1[i])) // checks lowercase letters
                low++;
            if(isdigit(str1[i])) // checks digits
                digit++;
            if (ispunct(str1[i])) // checks special characters
                special++;
        }

        if (strlen(str1) < 8)
            cout << "Must be at least 8 characters long.\n";
        if (up == 0)
            cout << "Must be at least 1 uppercase letter.\n";
        if (low == 0)
            cout << "Must be at least 1 lowercase letter.\n";
        if (digit == 0)
            cout << "Must have at least 1 digit.\n";
        if (special == 0)
            cout << "Must have 1 special character" << endl;
    }

Answer 1

从评论中，您可能想要这样的内容：

void criteraValidation(const string& str1, // Pass by const reference since it won't be modified.  
                       int& up, int& low, int& digit, int& special);  

    void criteraValidation(const string& str1,
                          int& up, int& low, int& digit, int& special)
    {
        up = 0;
        low = 0;
        digit = 0;
        special = 0;
        const std::string::size_type length = str1.length();
        for (int i = 0; i < length; i++)
        {
            if (isupper(str1[i])) // checks uppercase letters
                up++;
            if (islower(str1[i])) // checks lowercase letters
                low++;
            if(isdigit(str1[i])) // checks digits
                digit++;
            if (ispunct(str1[i])) // checks special characters
                special++;
        }

        if (str1.length() < 8)
            cout << "Must be at least 8 characters long.\n";
        if (up == 0)
            cout << "Must be at least 1 uppercase letter.\n";
        if (low == 0)
            cout << "Must be at least 1 lowercase letter.\n";
        if (digit == 0)
            cout << "Must have at least 1 digit.\n";
        if (special == 0)
            cout << "Must have 1 special character" << endl;
    }

主要：

do
{
    Upper = Lower = Digit = SpecialChar = 0;

    cout << "Enter password: ";
    cin.getline(password, SIZE);
    criteraValidation(password, Upper, Lower, Digit, SpecialChar);
}
while (SpecialChar == 0
       || Upper == 0
       || Lower == 0
       || Digit == 0
       || (password.length() < 8));

注意：isupper，islower，isdigit和ispunct是独占的（字符不能同时为大写和小写），所以你可能想要使用if-else-if阶梯，以便不是所有的比较都会被执行：

const char c = str1[i];
if (isupper(c))
{
   ++up;
}
else if (islower(c))
{
   ++low;
}
else if (isdigit(c))
{
   ++digit;
}
else if (ispunct(c))
{
   ++special;
}
else
{
  // Put code here for characters not of above types.
}

例如，对于字符“A”，只执行一个函数，而所有比较都在代码中执行。

Answer 2

您的示例显示strlen（）处理char数组。当您将其传递给函数时，您需要使用＆＃39;字符串＆＃39;进行发送。那是一个std :: string吗？你需要调用strlen（str1.c_str（））吗？

当我把它放入一个函数时，Strlen不工作

2 个答案: