c# 当imageList绑定到ListView时，imageList第一张图片不显示

Question

我有一个Listview 控制器与imageList 绑定Listview 项目和Imagelist 图像通过while 循环添加。 dataReader(). 的问题是在添加这两个项目后，Listview 项目显示正确但第一个图像未显示意味着图像从 2nd listview 项目开始。我用调试模式检查了每一件事。然后我对imagelist 感到困惑，因为它第一次运行时将COUNT 显示为1 然后下一个循环再次是COUNT 变成0，下一次它是1,2,3,4,5,6.... 等等。

private void populate(MySqlDataReader data)
        {
            //ImageList
            ImageList imgList = new ImageList();

            //set listview category items as Large icons
            listView_Category.View = View.LargeIcon;
            imgList.Images.Clear();

            //ADD image list into Listview
            listView_Category.LargeImageList = imgList;

            Application.DoEvents();

            int i = 0;
            while (data.Read())
            {
                try
                {
                    imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/" + data.GetString(2)));
                }
                catch (Exception w)
                {
                    MessageBox.Show(w.Message);
                }

                imgList.ImageSize = new Size(100, 100);
                imgList.ColorDepth = ColorDepth.Depth32Bit;

                listView_Category.Items.Add(data.GetString(1), i);
                i++;

            }
        }

我也尝试手动添加图像...当它不起作用时。只有它通过循环添加图像。是语言错误吗？

//imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-1.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-2.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-3.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-4.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-5.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-6.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-7.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-8.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-9.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-10.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-11.jpg"));
            //imgList.Images.Add(Image.FromFile(@"./" + populateFolder + "/image-12.jpg"));

数据库

Answer 1

请试试这个，这段代码会从一个文件夹中读取所有文件，并在列表视图中添加显示它。您只需要更改从 DB 读取它的逻辑。

    private void Form1_Load(object sender, EventArgs e)
    {
        var folderPath = @"c:\images\";
        DirectoryInfo dir = new DirectoryInfo(folderPath);

        var imageList = new ImageList();
        foreach (FileInfo file in dir.GetFiles())
        {
            try
            {
               imageList.Images.Add(Image.FromFile(file.FullName));
            }
            catch{
                Console.WriteLine("This is not an image file");
            }
        }
        this.listView1.View = View.LargeIcon;
        imageList.ImageSize = new Size(128, 128);
        this.listView1.LargeImageList = imageList;

        for (int j = 0; j < imageList.Images.Count; j++)
        {
            ListViewItem item = new ListViewItem();
            item.ImageIndex = j;
            this.listView1.Items.Add(item);
        }
    }