In my app, I have a few of checkListBoxes and I need to save clicks on this list. That means for the next time I don't need to click on them again and again.

Code:

public Form2()
{
    InitializeComponent();
    InitializeSecondForm();
}

private void InitializeSecondForm()
{
    this.Height = Properties.Settings.Default.SecondFormHeight;
    this.Width = Properties.Settings.Default.SecondFormWidth;
    this.Location = Properties.Settings.Default.SecondFormLocation;

    this.FormClosing  = SecondFormClosingEventHandler;
    this.StartPosition = FormStartPosition.Manual;
}

private void SecondFormClosingEventHandler(object sender, FormClosingEventArgs e)
{
    Properties.Settings.Default.SecondFormHeight = this.Height;
    Properties.Settings.Default.SecondFormWidth = this.Width;
    Properties.Settings.Default.SecondFormLocation = this.Location;

    Properties.Settings.Default.Save();
}

I tried to use this question for my answer, but it's not working: Save CheckedListBox Items to Settings

With a simple checkBox it's not a problem, but here we have a list.

Any idea how to do it?

CodePudding user response：

Perhaps saving identifiers of each checked item to a json file.

In the following I did on CheckedListBox, for multiple CheckedListBox controls you need to adjust the code to use one json file with a modified structure to account for multiple CheckedListBox control or one json file per CheckedListBox.

Example, load items into the following class

public class Product
{
    public int ProductID { get; set; }
    public string ProductName { get; set; }
    public override string ToString()
    {
        return ProductName;
    }

}

Use the following class for read/write to a json file, in this case using json.net but will work also with system.text.json.

public class JsonOperations
{
    /// <summary>
    /// In your app you need to setup a different file name for each CheckedListBox
    /// </summary>
    public static string FileName => 
        Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Checked.json");

    /// <summary>
    /// Save only checked products
    /// </summary>
    /// <param name="list"></param>
    public static void Save(List<ProductItem> list)
    {
        string json = JsonConvert.SerializeObject(list, Formatting.Indented);
        File.WriteAllText(FileName, json);
    }

    /// <summary>
    /// Read back if file exists
    /// </summary>
    /// <returns></returns>
    public static List<ProductItem> Read()
    {
        List<ProductItem> list = new List<ProductItem>();

        if (File.Exists(FileName))
        {
            list = JsonConvert.DeserializeObject<List<ProductItem>>(File.ReadAllText(FileName));
        }

        return list;
    }
}

The following classes provide methods to get checked items set checked items from json mentioned above.

public static class CheckedListBoxExtensions
{
    public static List<ProductItem> IndexList(this CheckedListBox sender)
    {
        return
        (
            from item in sender.Items.Cast<Product>()
                .Select(
                    (data, index) =>
                        new ProductItem()
                        {
                            ProductID = data.ProductID,
                            Index = index
                        }
                )
                .Where((x) => sender.GetItemChecked(x.Index))
            select item
        ).ToList();
    }
    public static void SetChecked(this CheckedListBox sender, int identifier, bool checkedState = true)
    {
        var result = sender.Items.Cast<Product>()
            .Select((item, index) => new CheckItem
            {
                Product = item, 
                Index = index
            })
            .FirstOrDefault(@this => @this.Product.ProductID == identifier);

        if (result != null)
        {
            sender.SetItemChecked(result.Index, checkedState);
        }
    }
}

public class CheckItem { public Product Product { get; set; } public int Index { get; set; } }

Form code would resemble the following to read checked items on form shown event and save checked item on form closing event.

public partial class SaveItemsForm : Form
{
    private List<Product> _products = new List<Product>();
    public SaveItemsForm()
    {
        InitializeComponent();
        Shown  = OnShown;
        Closing  = OnClosing;
    }

    private void OnClosing(object sender, CancelEventArgs e)
    {
        List<ProductItem> checkedItems = ProductCheckedListBox.IndexList();
        if (checkedItems.Count > 0)
        {
            JsonOperations.Save(checkedItems);
        }
        else
        {
            JsonOperations.Save(new List<ProductItem>());
        }
    }

    private void OnShown(object sender, EventArgs e)
    {
        _products = SqlServerOperations.ProductsByCategoryIdentifier(1);

        ProductCheckedListBox.DataSource = _products;

        /*
         * Search for each product by id, if in the CheckedListBox check it
         */
        var items = JsonOperations.Read();
        if (items.Count >0 )
        {
            items.ForEach( x => ProductCheckedListBox.SetChecked(x.ProductID));
        }
    }
}

CodePudding user response：

In such conditions, I prefer to have a simple database like SQLite. Use this database to save the user profile. user profile data will store all such data. for example, the user and password can be saved into that to remember to the user for next time login, or all settings and configurations that user selected it during using the system.