如何使用 C# 过滤 CSV

Question

我有一个包含 2 列的 csv，第一列包含字符串，第二列包含开始和结束时间（例如：11:00-22:00）。例如，您将如何尽可能高效地过滤包含 14:00 时间的字段？

例如：

餐厅名称营业时间

串鹤 11:30-21:00

大阪屋餐厅11:30-21:00

臭玫瑰9:00-22:00

我写 21:30 会显示 The Stinking Rose，或者如果我写 11:00 在控制台上显示 Kushi Tsuru、Osakaya Restaurant 和 The Stinking Rose。

class Filter
{
    static void Main(string[] args)
    {
        List<Restaurant> csvFile = File.ReadAllLines(@"C:\restaurant-hours.csv")
                                   .Skip(1)
                                   .Select(Restaurant.FromCsv)
                                   .ToList();

        void filter_by_hour()
        {
            Console.WriteLine("\nEnter the hour");
            string Dateofbirth = (Console.ReadLine();
            var filter_data = csvFile.Where(e => (DateTime.Parse(e.OpenHour)) > Dateofbirth)
                              .Select(e => e);
        }

    }
}

Answer 1

这比 LINQ 和 Lambda 函数更快。此外，可以删除许多变量，只是为了清楚起见才添加它们。已经测试，有效。

    static void Main(string[] args)
        {
            StreamReader reader = new StreamReader("a.txt");
            string[] time = Console.ReadLine().Split(':');
            int hour = 0;
            int minute = 0;

            try
            {
               hour = Convert.ToInt32(time[0]);
               minute = Convert.ToInt32(time[1]); 
            }
            catch
            {
               Console.WriteLine("The input must be something like aa:bb, with aa > 00 and aa < 24, bb >= 00 and bb <=53");
               return;
            }

            string[] first_time;
            string[] second_time;
            string[] time_frame;

            int first_hour;
            int first_minute;
            int second_hour;
            int second_minute;

            DateTime _date = new DateTime(1, 1, 1, hour, minute, 0);
            DateTime first_date, second_date;

            string line = "";
            string[] tokens;
            while ((line = reader.ReadLine()) != null)
            {
                tokens = line.Split(' ');
                time_frame = tokens[tokens.Length - 1].Split('-');
                first_time = time_frame[0].Split(':');
                first_hour = Convert.ToInt32(first_time[0]);
                first_minute = Convert.ToInt32(first_time[1]);

                first_date = new DateTime(1, 1, 1, first_hour, first_minute, 0);
                second_time = time_frame[1].Split(':');
                second_hour = Convert.ToInt32(second_time[0]);
                second_minute = Convert.ToInt32(second_time[1]);

                second_date = new DateTime(1, 1, 1, second_hour, second_minute, 0);

                if (_date >= first_date && _date <= second_date)
                {
                    for (int i = 0; i < tokens.Length - 1; i++)
                    {
                        Console.Write(tokens[i]);
                        Console.Write(" ");
                    }
                    Console.WriteLine("");
                }
            }    
            reader.Close();
        }

如何使用 C# 过滤 CSV

How to filter a CSV with C#

c#

console-application

.net-core