这是一个WPF MVVM 异步命名帮助类
- 实现异步命令绑定，包括暂停、取消、以及取消上一次命名的重载
- 也包含RelayCommand 和 RelayCommand 的常规命令和 NotifyTaskCompletion
- AsyncCommand 包含12个重载
AsyncCommand<object> Create(Func<Task> command, Func<bool> canExecute = null)
AsyncCommand<TResult> Create<TResult>(Func<Task<TResult>> command, Func<bool> canExecute = null)
AsyncCommand<object> Create(Func<CancellationToken, Task> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<TResult> Create<TResult>(Func<CancellationToken, Task<TResult>> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<object> Create(Func<CancellationToken, ManualResetEvent, Task> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<TResult> Create<TResult>(Func<CancellationToken, ManualResetEvent, Task<TResult>> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<T, object> Create<T>(Func<T, Task> command, Func<bool> canExecute = null)
AsyncCommand<T, TResult> Create<T, TResult>(Func<T, Task<TResult>> command, Func<bool> canExecute = null)
AsyncCommand<T, object> Create<T>(Func<T, CancellationToken, Task> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<T, TResult> Create<T, TResult>(Func<T, CancellationToken, Task<TResult>> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<T, object> Create<T>(Func<T, CancellationToken, ManualResetEvent, Task> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand<T, TResult> Create<T, TResult>(Func<T, CancellationToken, ManualResetEvent, Task<TResult>> command, Func<bool> canExecute = null, bool isCancelUpTask = false)
AsyncCommand使用方法
- 不带参数
private IAsyncCommand test1;
public IAsyncCommand Test1 => test1 ??= AsyncCommand.Create(async () => {
await Task.CompletedTask;
});
private IAsyncCommand test2;
public IAsyncCommand Test2 => test2 ??= AsyncCommand.Create(async token => {
await Task.CompletedTask;
});
private IAsyncCommand test3;
public IAsyncCommand Test3 => test3 ??= AsyncCommand.Create(async (token, manual) => {
await Task.CompletedTask;
});
- 带CommandParameter参数
private IAsyncCommand test1;
public IAsyncCommand Test1 => test1 ??= AsyncCommand.Create<Data>(async data => {
await Task.CompletedTask;
});
private IAsyncCommand test2;
public IAsyncCommand Test2 => test2 ??= AsyncCommand.Create<Data>(async (data, token) => {
await Task.CompletedTask;
});
private IAsyncCommand test3;
public IAsyncCommand Test3 => test3 ??= AsyncCommand.Create<Data>(async (data, token, manual) => {
manual.WaitOne();
if (token.IsCancellationRequested) return;
await Task.CompletedTask;
});
- 或者不使用async
private IAsyncCommand test1;
public IAsyncCommand Test1 => test1 ??= AsyncCommand.Create(() => {
return Task.CompletedTask;
});
- 执行前取消上一次命令
private IAsyncCommand test4;
public IAsyncCommand Test4 => test4 ??= AsyncCommand.Create(async token => {
if (token.IsCancellationRequested) return;
await Task.CompletedTask;
}, true);
- XAML界面我们可以使用
<TextBlock Text="{Binding Test1.Execution.Result}"/>
<TextBlock Text="{Binding Test1.Execution.IsCompleted}"/>
<TextBlock Text="{Binding Test1.Execution.IsNotCompleted}"/>
<TextBlock Text="{Binding Test1.Execution.IsSuccessfullyCompleted}"/>
<TextBlock Text="{Binding Test1.Execution.IsCanceled}"/>
<TextBlock Text="{Binding Test1.Execution.IsFaulted}"/>
<TextBlock Text="{Binding Test1.Execution.ErrorMessage}"/>
<Button Command = "{Binding Test1}" CommandParameter="111222">测试</Button>
<Button Command = "{Binding Test1.CancelCommand}" > 取消 </ Button >
<Button Command="{Binding Test1.ManualResetAsyncCommand}">暂停</Button>
<TextBlock Text = "{Binding Test1.IsSuspend}" />