CA1416 Warning after upgrading from .NET Framework 4.8 to .NET 8 with Windows Forms

Question

Hello,

I recently upgraded my project from .NET Framework 4.8 to .NET 8 and I’m using Windows Forms. Although I’m not getting any errors, I’m seeing some warnings that I would like to resolve.

One of the warnings is CA1416, which indicates that “MessageBoxIcon.Error” is only supported on “windows” 6.1 and later versions. Here is the full detail of the warning:

Severity Code Description Project File Line Suppression State Warning (active) CA1416 This call site is reachable on all platforms. “MessageBoxIcon.Error” is only supported on “windows” 6.1 and later versions. (https://learn.microsoft.com/dotnet/fundamentals/code-analysis/quality-rules/ca1416) PresentationLayer D:\Documents\Visual Studio 2022\Repositories\SmartPOS\PresentationLayer\Sequential\FrmSequentialDocument.cs 147

In addition, I would like to mention that I plan to run my application on platforms other than Windows in the future.

Could anyone help me understand how I can resolve this warning and ensure that my application is compatible with other platforms?

Thanks in advance for any help you can provide.

Roberto Melgar

Answer 1

Windows forms is not cross platform but for Windows Forms look at TaskDialog. Some examples. The Owner parameter can be the form or any visible control on the form.

namespace ErrorExampleApp.Classes;
public static class CustomDialogs
{
    public static void ErrorBox(Control owner, Exception exception, string buttonText = "OK")
    {

        TaskDialogButton button = new(buttonText);

        var text = $"Encountered the following{Environment.NewLine}{exception.Message}";

        TaskDialogPage page = new()
        {
            Caption = "Error",
            SizeToContent = true,
            Heading = text,
            Icon = TaskDialogIcon.Error,
            Buttons = [button]
        };

        TaskDialog.ShowDialog(owner, page);

    }

    public static void InformationBox(Control owner, string heading, string buttonText = "Ok")
    {

        TaskDialogButton okayButton = new(buttonText);

        TaskDialogPage page = new()
        {
            Caption = "Information",
            SizeToContent = true,
            Heading = heading,
            Icon =  TaskDialogIcon.Information,
            Buttons = [okayButton]
        };

        TaskDialog.ShowDialog(owner, page);

    }

    public static bool Question(Control owner, string heading)
    {

        TaskDialogButton yesButton = new("Yes") { Tag = DialogResult.Yes };
        TaskDialogButton noButton = new("No") { Tag = DialogResult.No };

        var buttons = new TaskDialogButtonCollection
        {
            noButton,
            yesButton
        };

        TaskDialogPage page = new()
        {
            Caption = "Question",
            SizeToContent = true,
            Heading = heading,
            Icon = TaskDialogIcon.Information,
            Buttons = buttons
        };

        var result = TaskDialog.ShowDialog(owner, page);

        return (DialogResult)result.Tag! == DialogResult.Yes;

    }
}

Usage

private void ErrorSampleButton_Click(object sender, EventArgs e)
{
    try
    {
        var lines = File.ReadAllLines("C:\\Files\\Payne.txt");
    }
    catch (Exception exception)
    {
        CustomDialogs.ErrorBox(this, exception);
    }
}

You can use your own images for the Icon property from project resources e.g.

public static void ErrorBox(Control owner, Exception exception, string buttonText = "OK")
{

    TaskDialogButton button = new(buttonText);

    var text = $"Encountered the following{Environment.NewLine}{exception.Message}";

    TaskDialogPage page = new()
    {
        Caption = "Error",
        SizeToContent = true,
        Heading = text,
        Icon = new TaskDialogIcon(Properties.Resources.Explaination),
        Buttons = [button]
    };

    TaskDialog.ShowDialog(owner, page);

}

Example

Answer 2

Very clear answer, thank you very much.