C# 日期时间格式和比较

Question

我正在为我的大学编写课程安排程序，我在使用 C# 进行比较时遇到了一些麻烦。对于每门课程，给定的日期时间采用如下字符串格式：

 string Start_Time = "10:00";
 string End_Time = "10:50";

我需要将它们转换为 DateTime 格式（最好限制为 HH:mm），然后进行比较以确保课程之间没有重叠。我当前要检查的代码如下所示。

static bool checkTimes(Courses courseOne, Courses courseTwo)
    {
        bool overlapChecker = false;

        // Get comparison values for course times
        DateTime s1 = Convert.ToDateTime(courseOne.Start_Time);
        DateTime s2 = Convert.ToDateTime(courseTwo.Start_Time);
        DateTime e1 = Convert.ToDateTime(courseOne.End_Time);
        DateTime e2 = Convert.ToDateTime(courseTwo.End_Time);

        // Check for overlapping days of the week
        foreach (char c1_days in courseOne.Days)
        {
            foreach (char c2_days in courseTwo.Days)
            {
                if (c1_days == c2_days)
                {
                    overlapChecker = true;
                }
            }
        }

        // If there are any overlapping days, compare DateTimes of courses for overlap
        if (overlapChecker == true)
        {
            // Compare all possibilities of time overlap
            if ((s2 >= s1 && s2 <= e1) || (e1 >= s1 && e1 <= e2))
            {
                return true;
            }
        }
        return false;
    }

目前，这不起作用。我不太确定哪里出了问题，但我们将不胜感激任何帮助。谢谢！

Answer 1

你可以2步。首先 => 在模型 "Courses" 中创建将字符串转换为日期时间的方法，例如：

public DateTime StartTime()
{
    return new DateTime(2018,6,18,this.Start_Time.split(':')[0],this.Start_Time.split[1]);
}

第二个 => 重写课程的 equals 方法：

public override bool equals(object entity)
{
    var temp = entity as Courses;
    if (temp == null) return false;
    //Logics for a Course is equal to another Course
    If (this.StartTime == temp.StartTime)
        return true;
    return false;
}

而且你不能有方法 "CheckTimes"，只需调用：

bool result = CourseOne.equals ( CouseTwo );

Answer 2

我在这里做了一个几乎没有假设的 rextester - http://rextester.com/UDI9335

假设：

你的Courseclass如下

public class Course {
    public string cName { get; set; }
    public string Start_Time { get; set; }
    public string End_Time { get; set; }
    public List<string> Days { get; set; }
}

classes 在所有给定的日子里同时发生。（根据您的代码）
Days 是 strings 的 List，我暂时想到了像 M, T, W, T, F 这样的字符列表或数组，但这会给出不正确的结果，因为 [=17] =] 正在重复。周二和周四

代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
using System.Globalization;

namespace Rextester
{
    public class Program
    {
        public static void Main(string[] args)
        {

            Course c1 = new Course{
                cName = "Course 1",
                Start_Time = "10:00",
                End_Time = "10:50",
                Days = new List<string>{ "Mon", "Tue", "Wed"}
            };

            Course c2 = new Course{
                cName = "Course 2",
                Start_Time = "10:40",
                End_Time = "11:20",
                Days = new List<string>{ "Wed", "Thu", "Fri"}
            };

            Course c3 = new Course{
                cName = "Course 3",
                Start_Time = "11:30",
                End_Time = "12:20",
                Days = new List<string>{ "Mon", "Tue", "Fri"}
            };


            bool areC1C2Clashing = areCoursesClashing(c1, c2);
            Console.WriteLine("Are c1 & c2 clashing - " + areC1C2Clashing);
            Console.WriteLine();

            bool areC2C3Clashing = areCoursesClashing(c2, c3);
            Console.WriteLine("Are c2 & c3 clashing - " + areC2C3Clashing);
            Console.WriteLine();

            bool areC1C3Clashing = areCoursesClashing(c1, c3);
            Console.WriteLine("Are c1 & c3 clashing - " + areC1C3Clashing);
            Console.WriteLine();
        }

        public static bool areCoursesClashing(Course cA, Course cB){
            bool clashDetected = false;
            foreach(var coruseDay in cA.Days){
                if(cB.Days.Contains(coruseDay)){

                    DateTime cAStartTime = DateTime.ParseExact(cA.Start_Time, "HH:mm", CultureInfo.InvariantCulture);
                    DateTime cAEndTime = DateTime.ParseExact(cA.End_Time, "HH:mm", CultureInfo.InvariantCulture);
                    DateTime cBStartTime = DateTime.ParseExact(cB.Start_Time, "HH:mm", CultureInfo.InvariantCulture);
                    DateTime cBEndTime = DateTime.ParseExact(cB.End_Time, "HH:mm", CultureInfo.InvariantCulture);

                    if( cAStartTime < cBEndTime && cBStartTime < cAEndTime){
                        Console.WriteLine("WARNING!!! Classes clash for --> " + cA.cName + " & " + cB.cName);
                        clashDetected = true;
                    }
                }
            }
            return clashDetected;
        }
    }

    public class Course {
        public string cName { get; set; }
        public string Start_Time { get; set; }
        public string End_Time { get; set; }
        public List<string> Days { get; set; }
    }
}

输出：

WARNING!!! Classes clash for --> Course 1 & Course 2

Are c1 & c2 clashing - True

Are c2 & c3 clashing - False

Are c1 & c3 clashing - False

C# 日期时间格式和比较

C# DateTime Format and Comparison

c#

datetime

boolean

comparison

overlap