//////asyncDelegate asyncDelegateTask; 全局变量
/// <summary>
/// 申明供异步委托调用的任务回调函数，即根据任务完成情况做出响应
/// </summary>
/// <param name="iAsyncResult"></param>
private void callBackAsyncDelegate(IAsyncResult iAsyncResult)
{
if (true)
{
////while (!iar.IsCompleted)
////{
//// //这里可以执行其他代码
////}
AsyncObjectStateClass asyncObjectState = (AsyncObjectStateClass)(iAsyncResult.AsyncState);//通过AsyncState获取传入的object
AsyncResult result = (AsyncResult)iAsyncResult;
asyncDelegate caller = (asyncDelegate)result.AsyncDelegate; //任务执行函数
AsyncMethodReturnObject asyncMethodReturnObject = caller.EndInvoke(iAsyncResult); //通过EndInvoke获取异步结果，注意每个asyncDelegate的EndInvoke只能使用一次。
if (ShowMessageInAsyncCallbackDemo != null)
{
ShowMessageInAsyncCallbackDemo(this, asyncObjectState.message);
ShowMessageInAsyncCallbackDemo(this, (asyncMethodReturnObject).returnObject.ToString());
}
else
{
}
}
else
{
iAsyncResult.AsyncWaitHandle.WaitOne();//等待方法调用的完成
}
}
public async Task taskStartAsyncDelegate(object sleepMS)
{
if (true)
{
await Task.Run(() =>
{
AsyncMethodParameterObject asyncMethodParameterObject = new AsyncMethodParameterObject(sleepMS);
asyncDelegate asyncDelegateTask = new asyncDelegate(asyncMethodTask);
AsyncCallback asyncCallback = new AsyncCallback(callBackAsyncDelegate);
AsyncObjectStateClass asyncObjectState = new AsyncObjectStateClass(sleepMS); //实例化类，该对象可以传入回调函数中
IAsyncResult iar = (AsyncResult)asyncDelegateTask.BeginInvoke(asyncMethodParameterObject, asyncCallback, asyncObjectState); //异步执行Method，界面不会假死，后执行回调函数，弹出提示框
});
}
else //lambda形式
{
await Task.Run(() =>
{
//回调函数callback方法可以改写成lambda形式
//AsyncMethodParameterObject asyncMethodParameterObject = new AsyncMethodParameterObject(sleepMS);
new asyncDelegate(asyncMethodTask).BeginInvoke(new AsyncMethodParameterObject(sleepMS), ar =>
{ //回调函数写成了lambda形式
// Retrieve the delegate.
AsyncResult result = (AsyncResult)ar;
asyncDelegate caller = (asyncDelegate)result.AsyncDelegate;
// Retrieve the format string that was passed as state information.
AsyncObjectStateClass asyncObjectState = (AsyncObjectStateClass)ar.AsyncState;//通过AsyncState获取传入的object
// Call EndInvoke to retrieve the results.
AsyncMethodReturnObject asyncMethodReturnObject = caller.EndInvoke(ar);
//MessageBox.Show(formatString.ToString() + "\n\r" + returnValue);
}, new AsyncObjectStateClass("Return String"));
});
}
}
