在WinForms中线程安全且快速地向ListView添加20000个项

我有一个自定义的WinForms控件,其中包含一个ListView,该ListView必须从CSV文件中读取多达20000个项目。

我使用CSVHelper在单独的线程中加载文件,然后调用 listView1.Add 在UI线程上添加它们 ListView .

我目前的实现(如您在代码中看到的)可能很糟糕,因此在将这20000个项目添加到 ListView .

请注意,我对线程安全和多线程开发相当陌生。

这是我的自定义控件的整个代码:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Globalization;
using CsvHelper;
using System.IO;
using System.Threading;

namespace MyDevTaskDesktop
{
    public partial class MyCSVReaderControl : UserControl
    {
        List<Product> loadedProducts;

        public MyCSVReaderControl()
        {
            InitializeComponent();
        }

        private void BtnBrowse_Click(object sender, EventArgs e)
        {
            CsvFileDialog.ShowDialog();
        }

        private void CsvFileDialog_FileOk(object sender, CancelEventArgs e)
        {
            TxtFilename.Text = CsvFileDialog.FileName;

            listView1.Items.Clear();

            listView1.Visible = false;
            listView1.View = View.Details;
            listView1.AllowColumnReorder = true;
            listView1.GridLines = true;
            listView1.Sorting = SortOrder.Ascending;
            listView1.FullRowSelect = true;
            listView1.AllowColumnReorder = true;

            listView1.Columns.Add("#", 50, HorizontalAlignment.Left);
            listView1.Columns.Add("Filename", 100, HorizontalAlignment.Left);
            listView1.Columns.Add("Id", 100, HorizontalAlignment.Left);
            listView1.Columns.Add("Quantity", 50, HorizontalAlignment.Right);
            listView1.Columns.Add("Price", 50, HorizontalAlignment.Right);

            LoadCSVThread();

            loadedProducts = new List<Product>();
        }
        public void LoadCSV()
        {
            using (var reader = new StreamReader(CsvFileDialog.FileName))
            using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
            {
                csv.Configuration.HasHeaderRecord = false;
                csv.Configuration.IgnoreBlankLines = true;
                csv.Configuration.BadDataFound = null;
                csv.Configuration.AutoMap<CsvProduct>();
                csv.Configuration.Delimiter = ";";

                var records = csv.GetRecords<CsvProduct>().ToList();

                int index = 0;
                string firstFilename = null;
                Color foreColor;

                foreach (CsvProduct product in records)
                {
                    index++;

                    if (firstFilename == null)
                    {
                        firstFilename = product.Filename;
                    }

                    foreColor = (firstFilename == product.Filename) ? Color.Red : Color.Blue;

                    loadedProducts.Add(new Product()
                    {
                        Color = foreColor,
                        Index = index,
                        Filename = product.Filename,
                        Id = product.Id,
                        Quantity = product.Quantity,
                        Price = product.Price
                    });

                    if (LblProcess.InvokeRequired)
                    {
                        LblProcess.Invoke((MethodInvoker)delegate ()
                        {
                            LblProcess.Text = "Processed " + index + " records...";
                        });
                    }
                }

                if (LblProcess.InvokeRequired)
                {
                    LblProcess.Invoke((MethodInvoker)delegate ()
                    {
                        LblProcess.Text = "Finished!";
                        LblProcess.Visible = false;
                    });
                }

                if (listView1.InvokeRequired)
                {
                    listView1.Invoke((MethodInvoker)delegate ()
                    {
                        listView1.Visible = true;

                        listView1.BeginUpdate();

                        foreach (var item in loadedProducts)
                        {
                            ListViewItem listItem = new ListViewItem(new string[]
                            {
                                item.Index.ToString(),
                                item.Filename,
                                item.Id,
                                item.Quantity.ToString(),
                                item.Price.ToString()
                            });

                            listItem.ForeColor = item.Color;

                            listView1.Items.Add(listItem);
                            //listView1.EnsureVisible(listView1.Items.Count - 1);
                        }

                        listView1.Sort();
                        listView1.EndUpdate();
                    });
                }
            }
        }

        public void LoadCSVThread()
        {
            Thread worker = new Thread(LoadCSV);
            worker.IsBackground = true;
            worker.SetApartmentState(ApartmentState.STA);
            worker.Start();
        }

        private class Product
        {
            public Color Color { get; set; }
            public int Index { get; set; }
            public string Filename { get; set; }
            public string Id { get; set; }
            public int Quantity { get; set; }
            public double Price { get; set; }
        }

        private class CsvProduct
        {
            public string Filename { get; set; }
            public string Id { get; set; }
            public int Quantity { get; set; }
            public double Price { get; set; }
        }
    }
}

我也试过 async/await ,但最终由于我尚不清楚的原因而变得更慢。当我使用这些时,UI中的任何内容在迭代数组时都没有更新。

我知道我的方法来填补 loadedProducts List 首先迭代该列表以更新视图是不好的,但目前这会产生最快的结果——这是我能做的最好的事情,因为如果我在更新的同时更新UI LblProcess 标签文本,它会变慢,加倍。

那么,将20000个或更多项目添加到 ListView ?