Question

我想知道如何检查我输入的日期是否有效。

public static bool JeVeljavenDatum(int dan, int mesec, int leto)
    {
        return dan > 0 && dan <= 31 && mesec > 0 && mesec <= 12 && leto > 0 && leto <= DateTime.Today.Year;

    }

如上所示，我并不认为该功能是检查日期的最佳方法，因此欢迎您提出任何提示：）

问题在于检查年份是否为leap年，以及月份是否只有30天或31。或者是使用long if方法检查这种情况的唯一方法。

if ((Mesec == 1 || Mesec == 3 || Mesec == 5 || Mesec == 7 || Mesec == 8 || Mesec == 10 || Mesec == 12) && Dan == 31)
        {
            Dan = 1;
            Mesec++;

            if (Mesec == 12)
            {
                Mesec = 1;
                Leto++;
            }

        }

        if ((Mesec == 4 || Mesec == 6 || Mesec == 9 || Mesec == 11) && Dan == 30)
        {
            Dan = 1;
            Mesec++;

            if (Mesec == 12)
            {
                Mesec = 1;
                Leto++;
            }

        }

Answer 1

尝试使用检查数字的constructor创建正确的DateTime。

#include <cs50.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>

int validate (int c, string v[]); //prototpe validate function

int main (int argc, string argv[])
{
    int validate (int argc, string argv[]); //run validate for argc and argv

    printf("Key is valid\n"); //if valid, print message

}

int validate (int c, string v[])
{
    //Validate that only one Command Line Argument was entered
    if (c != 2) //Check the number if entered commands at execution
    {
        //If more than one, print error message
        printf("Key must be the only Command Line Argument\n");
        return 1; //Return false
    }

    //Validate that Key length is 26 characters
    if (strlen(v[1]) != 26) //Don't forget null 0
    {
        printf("Key must contain exactly 26 characters\n");
        return 1; //Return false
    }

    //Validate that all Key characters are alphabetic
    for (int i = 0, n = strlen(v[1]); i < n; i++)
    {
        //Check each element of the array
        if (isalpha(v[1][i]))
        {
            continue; //Continue if alphabetic
        }
        else
        {
            //if non-alphabetic, print error code
            printf("Key must contain only alphabetic characters\n");
            return 1; //Return false
        }
    }

    //Validate that each Key character is unique
    for (int x = 0, z = strlen(v[1]) - 1; x < z; x++)
    {
        //Create a second loop to compare every element to the first before incrementing the first
        for (int y = x + 1; y < z; y++)
        {
            //Cast array elements to int, check if each element equals next element in array
            if (v[1][x] == v[1][y])
            {
                printf("Key must contain exactly 26 unique characters\n");
                return 1;
            }
        }
    }

    return 0; //Key is valid, so return true
}

如何检查输入的日期是否有效

1 个答案: