Demonstrate how to export data to excel file through ClosedXML

ExcelExport.cs

using ClosedXML.Excel;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace Demo.Excel.Export
{
    class Program
    {
        static void Main(string[] args)
        {
            // generate fake data from the help of Bogus
            var users = GenerateFakeMembers(1000);
            // generate file: contact.xlxs
            GenerateContactSheet(users);

        }
        
        private List<Member> GenerateFakeMembers(int amount)
        {   
            var faker = new Faker<Member>("en");
            // rule for create field data
            // ...
            var users = faker.Generate(amount);
            return users;
        }

        private static void GenerateContactSheet(List<Member> users)
        {
            var wb = new XLWorkbook();
            var saveAsPath = Path.Combine($@"{AppDomain.CurrentDomain.BaseDirectory}\excels\", @"contact.xlsx");
            // set sheet name
            var worksheet = wb.Worksheets.Add("Contact List");
            // insert for the header from beginning
            users.Insert(0, new Member
            {
                FullName = nameof(Member.FullName),
                Sex = nameof(Member.Sex),
                Birthday = nameof(Member.Birthday),
                Phone = nameof(Member.Phone),
                Type = nameof(Member.Type)
            });
            // insert all data to sheet
            worksheet.Cell(1, 1).InsertData(users.Select(x => new
            {
                x.FullName,
                x.Sex,
                x.Birthday,
                x.Phone,
                x.Type
            }));

            // stying the worksheet
            // stying header
            worksheet.RangeUsed().FirstRowUsed().Style.Font.FontColor = XLColor.White;
            worksheet.RangeUsed().FirstRowUsed().Style.Fill.BackgroundColor = XLColor.FromArgb(79, 129, 189); // Blue, Accent 1
            worksheet.RangeUsed().FirstRowUsed().Style.Font.Bold = true;
            // stying font
            worksheet.RangeUsed().Style.Font.FontName = "Calibri";
            // stying alternate row colors except header row
            worksheet.RangeUsed().AddConditionalFormat()
                .WhenIsTrue("=MOD((ROW() + 1),2)=1").Fill.BackgroundColor = XLColor.FromArgb(217, 228, 240); // Blue, Accent 1, Lighter 80% 
            // set filter
            worksheet.RangeUsed().SetAutoFilter();
            
            // adjust contents width and height
            worksheet.Rows().AdjustToContents();
            worksheet.Columns().AdjustToContents();

            // save to file
            wb.SaveAs(saveAsPath);
        }
    }

    public class Member
    {
        public Guid UserId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public DateTime? DateOfBirth { get; set; } = null;
        public string Phone { get; set; }
        public DataSets.Name.Gender? Gender { get; set; } = null;
        public string Type { get; set; }
        // FirstName + "" LastName
        public string FullName { get; set; }
        public string Sex
        {
            get => Gender.HasValue ? Gender.Value.ToString() : nameof(this.Sex);
            set { }
        }
        public string Birthday
        {
            get => DateOfBirth.HasValue ? DateOfBirth.Value.ToString("yyyy-MM-dd") : nameof(this.Birthday);
            set { }
        }
    }

    public enum ContactType
    {
        Personal,
        Business,
        Faimly,
    }

}