求知若饥，虚心若愚

视频链接，Github链接

 using System;
using System.Collections.Generic;

namespace ReportingReflection
{
    public enum Rating { Rubbish, Poor, Average, Good, Excellent}

    public class Book
    {
        [ReportItem (2)]
        public string Author { get; set; }

        [ReportItem(1)]
        public string Title { get; set; }

        [ReportItem(3, Heading = "Date of Publication", Format = "dd-MM-yyyy")]
        public DateTime DateOfPublication { get; set; }

        [ReportItem(4)]
        public Rating Rating { get; set; }
    }

    public static class BookData
    {
        public static IEnumerable<Book> Books = new Book[]
        {
           new () {Title  = "Goldfinger", Author="Ian Fleming", DateOfPublication = new DateTime(1959, 3, 23), Rating = Rating.Excellent},
           new () {Title  = "Dr No", Author="Ian Fleming", DateOfPublication = new DateTime(1958, 3, 31), Rating = Rating.Good},
           new () {Title  = "Live and Let Die", Author="Ian Fleming", DateOfPublication = new DateTime(1954, 4, 5), Rating = Rating.Average},
           new () {Title  = "Emma", Author="Jane Austen", DateOfPublication = new DateTime(1815, 12, 23), Rating = Rating.Good},
           new () {Title  = "Persuasion", Author="Jane Austen", DateOfPublication = new DateTime(1818, 1, 1), Rating = Rating.Excellent},
           new () {Title  = "Great Expectations", Author="Charles Dickens", DateOfPublication = new DateTime(1861, 1, 1), Rating = Rating.Excellent},
           new () {Title  = "Oliver Twist", Author="Charles Dickens", DateOfPublication = new DateTime(1838, 1, 1), Rating = Rating.Average}
        };
    }
}

 using System.Collections.Generic;

namespace ReportingReflection
{
    public class Weather
    {
        [ReportItem(1)]
        public string City { get; set; }

        [ReportItem(2)]
        public string Description { get; set; }

        [ReportItem(3, Heading = "Temperature", Units = "°C")]
        public double TemperatureCentrigrade { get; set; }

        [ReportItem(4, Heading = "Rainfall", Units = " Inches", Format = "N2")]
        public double RainfallInches { get; set; }
    }

    public static class WeatherData
    {
        public static IEnumerable<Weather> Weather = new Weather[]
        {
            new () { City = "London", Description = "Sunny spells", TemperatureCentrigrade = 19, RainfallInches = 0 },
            new () { City = "Paris", Description = "Very hot", TemperatureCentrigrade = 27, RainfallInches = 0 },
            new () { City = "New York", Description = "Heavy rain", TemperatureCentrigrade = 8, RainfallInches = 6.598 },
            new () { City = "Munich", Description = "Foggy", TemperatureCentrigrade = 12, RainfallInches = 2.134 },
            new () { City = "Istanbul", Description = "Sunshine and showers", TemperatureCentrigrade = 22, RainfallInches = 8.5 },
            new () { City = "Santiago", Description = "Strong winds", TemperatureCentrigrade = 15, RainfallInches = 0.125 },
        };
    }
}

 using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;

namespace ReportingReflection
{
    public class CSVGenerator<T>
    {
        private IEnumerable<T> _data;
        private string _filename;
        private Type _type;

        public CSVGenerator(IEnumerable<T> data, string filename)
        {
            _data = data;
            _filename = filename;

            _type = typeof(T);
        }

        public void Generate()
        {
            var rows = new List<string>();

            rows.Add(CreateHeader());

            foreach (var item in _data)
                rows.Add(CreateRow(item));

            File.WriteAllLines($"{_filename}.csv", rows, Encoding.UTF8);
        }

        private string CreateHeader()
        {
            var properties = _type.GetProperties(BindingFlags.Public | BindingFlags.Instance);

            var orderedProps = properties.OrderBy(p => p.GetCustomAttribute<ReportItemAttribute>().ColumnOrder);

            var bob = new StringBuilder();

            foreach (var prop in orderedProps)
            {
                var attr = prop.GetCustomAttribute<ReportItemAttribute>();

                bob.Append(attr.Heading ?? prop.Name).Append(",");
            }

            return bob.ToString()[..^1];
        }

        private string CreateRow(T item)
        {
            var properties = _type.GetProperties(BindingFlags.Public | BindingFlags.Instance);

            var orderedProps = properties.OrderBy(p => p.GetCustomAttribute<ReportItemAttribute>().ColumnOrder);

            var bob = new StringBuilder();

            foreach (var prop in orderedProps)
            {
                bob.Append(CreateItem(prop, item)).Append(",");
            }

            return bob.ToString()[..^1];
        }

        private string CreateItem(PropertyInfo prop, T item)
        {
            var attr = prop.GetCustomAttribute<ReportItemAttribute>();

            return string.Format($"{{0:{attr.Format}}}{attr.Units}", prop.GetValue(item));
        }
    }

}

using System;

namespace ReportingReflection
{
    [AttributeUsage (AttributeTargets.Property)]
    public class ReportItemAttribute : Attribute
    {
        public string Heading { get; set; }
        public string Units { get; set; }
        public string Format { get; set; }
        public int ColumnOrder { get; }

        public ReportItemAttribute(int columnOrder)
        {
            ColumnOrder = columnOrder;
        }
    }
}

 using System;

namespace ReportingReflection
{
    class Program
    {
        static void Main()
        {
            new CSVGenerator<Book>(BookData.Books, "Books").Generate();
            new CSVGenerator<Weather>(WeatherData.Weather, "Weather").Generate();
        }
    }
}