为创建的每个图片框创建一个 picturebox_clicked 事件

Question

 private Form1 form1 { get; set; }
    readonly HttpClient httpClient = new();
    public static string FolderPath = @".\Storage";
    public static int picNum = 0;
    public static List<string> outofScopeURL = new List<string>();
    
    private async void Detailed_View_Load_1(object sender, EventArgs e)
    {
        DirectoryInfo directory = new(FolderPath);
        FileInfo[] files = directory.GetFiles();
        string[] FileFormats = { ".png", ".jpg", ".jpeg", ".txt" };
        for (int pictureCreator = 0; pictureCreator < files.Length; pictureCreator++)
        {
            FileInfo file = files[pictureCreator];
            if (file.FullName.EndsWith(FileFormats[3])) 
            {
                string url = File.ReadAllText(file.FullName);
                if (url != null)
                {
                    try
                    {
                        Image gif = Image.FromStream(await httpClient.GetStreamAsync(url));
                        PictureBox picture = new PictureBox
                        {
                            Name = url,
                            Size = new(38, 38),
                            Image = gif,
                            Location = new((gif.Width * pictureCreator), 0),
                            SizeMode = PictureBoxSizeMode.Zoom
                        };
                        this.Controls.Add(picture);
                        MessageBox.Show(picture.Name);
                        outofScopeURL.Add(url);
                        picture.Click += Picture_Click;
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show(ex.Message);
                    }
                }
                picNum++;
            }
        }
    }

What I'm trying to achieve: I'm trying to look in a specific directory for text files, then I want to read the files and extract the URL present in them. After I got all of the URLs of all the text files present in my folder, I added them into a list so I could use them with their respective picturebox

For example, when URL1 has picture1 and URL2 has picture2, I want to set the text of the clipboard to URL1 when picturebox1 that has picture1 applied to it is clicked.

What I have tried: I have tried making a new picturebox_Clicked event in the pictureCreator for loop but the problem is that the event is always applied to the last picturebox created.

Any help is much appreciated.

Answer 1

Your question is about creating a picturebox_clicked event for each picturebox created .

The code you posted seems to be doing that but as mentioned in the comments, casting the sender argument would be the key to making event useful. Consider a click handler implemented similar to this:

private void onAnyPictureBoxClick(object? sender, EventArgs e)
{
    if(sender is PictureBox pictureBox)
    {
        var builder = new List<string>();
        builder.Add($"Name: {pictureBox.Name}");
        builder.Add($"Tag: {pictureBox.Tag}");
        builder.Add($"Image Location: {pictureBox.ImageLocation}");
        MessageBox.Show(string.Join(Environment.NewLine, builder));
    }
}

Now give it a test (simulating the part where the URLs are already collected from the local store).

public partial class MainForm : Form
{
    public MainForm() =>InitializeComponent();
    protected override void OnLoad(EventArgs e)
    {
        base.OnLoad(e);
        int id = 0;
        // Here we have "already read" the URLs from the local store.
        foreach (var url in new string[] 
        {
            "https://i.stack.imgur.com/eSiWr.png",
            "https://i.stack.imgur.com/o5dmA.png",
            "https://i.stack.imgur.com/aqAuN.png",
        })
        {
            var dynamicPB = new PictureBox
            {
                Width = flowLayoutPanel.Width - SystemInformation.VerticalScrollBarWidth,
                Height = 200,
                SizeMode = PictureBoxSizeMode.Zoom,
                BackColor = Color.Azure,
                // In this case, the url is already stored here...
                ImageLocation = url,
                // ...but here are a couple of other ID options.
                Name = $"pictureBox{++id}",
                Tag = $"Tag Identifier {id}",
                Padding = new Padding(10),
            };
            dynamicPB.Click += onAnyPictureBoxClick;
            flowLayoutPanel.Controls.Add(dynamicPB);
        }
    }
    .
    .
    .
}