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void only for event handlers avoid

Context: async void should be used only for event handlers. For all other async methods, return Task or Task<T>.

using System;
using System.Threading.Tasks;
using System.Windows.Forms; // WinForms example

public partial class MyForm : Form
{
    // Acceptable: event handler
    private async void Button_Click(object sender, EventArgs e)
    {
        await LoadDataAsync();
    }

    private async Task LoadDataAsync()
    {
        await Task.Delay(100);
    }
}

Why avoid `async void`

Exceptions cannot be caught by the caller; they crash the process.
Hard to test (no task to await).
Caller cannot know when the method completes.

Real-world usage example

UI event handlers: WPF, WinForms, and Blazor allow async void for events because the framework handles the exception.

Example: Async void pitfalls