45 lines
1.2 KiB
C#
45 lines
1.2 KiB
C#
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using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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using System.Threading.Tasks;
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using System.Windows.Input;
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namespace Hopetry.Services
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{
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public class AsyncRelayCommand : ICommand
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{
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private readonly Func<Task> _executeAsync;
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private readonly Func<bool> _canExecute;
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public AsyncRelayCommand(Func<Task> executeAsync, Func<bool> canExecute = null)
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{
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_executeAsync = executeAsync ?? throw new ArgumentNullException(nameof(executeAsync));
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_canExecute = canExecute;
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}
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public event EventHandler CanExecuteChanged;
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// 这个方法决定了命令是否可执行
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public bool CanExecute(object parameter)
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{
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return _canExecute == null || _canExecute();
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}
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// 异步执行命令
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public async void Execute(object parameter)
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{
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if (_executeAsync != null)
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{
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await _executeAsync(); // 执行异步操作
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}
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}
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// 通知命令的可执行状态发生变化
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public void RaiseCanExecuteChanged()
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{
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CanExecuteChanged?.Invoke(this, EventArgs.Empty);
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}
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}
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}
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