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`[DelegateCommand]`

Generates DelegateCommand / DelegateCommand<T> or AsyncDelegateCommand / AsyncDelegateCommand<T> from instance methods.

Supported execute shapes (summary)

void with zero or one parameter → DelegateCommand / DelegateCommand<T>
Task (non-generic), Task<TResult>, ValueTask, ValueTask<TResult> → AsyncDelegateCommand (ValueTask family via .AsTask(); Task<TResult> via async lambda that awaits execute)
CanExecute = nameof(...) → bool method or compatible delegate (PSG2003, PSG2006 when invalid)

CancellationToken + ValueTask / ValueTask<TResult> / Task<TResult> is not supported (PSG1001).

Example

csharp

public partial class MainViewModel : BindableBase
{
    [DelegateCommand]
    private void Increment() { }

    [DelegateCommand]
    private async Task LoadAsync() { }

    [DelegateCommand(CanExecute = nameof(CanSubmit))]
    private void Submit() { }

    private bool CanSubmit() => true;
}

C# 14+ vs earlier

C# 14+: command properties can use the field keyword (no separate backing field).
Earlier: traditional _command??= lazy field pattern.