.net 4 使用System.Threading.Tasks

.net 4.5以上支持System.Threading.Tasks功能，4.0支持不全，可以通过配置解决

1. Task.Run(), Task.Delay().Wait()

 

public class TaskEx
    {
        public static Task Run(Action action)
        {
            var tcs = new TaskCompletionSource<object>();
            new Thread(() => {
                try
                {
                    action();
                    tcs.SetResult(null);
                }
                catch (Exception ex)
                {
                    tcs.SetException(ex);
                }
            })
            { IsBackground = true }.Start();
            return tcs.Task;
        }
        public static Task<TResult> Run<TResult>(Func<TResult> function)
        {
            var tcs = new TaskCompletionSource<TResult>();
            new Thread(() =>
            {
                try
                {
                    tcs.SetResult(function());
                }
                catch (Exception ex)
                {
                    tcs.SetException(ex);
                }
            })
            { IsBackground = true }.Start();
            return tcs.Task;
        }
        public static Task Delay(int milliseconds)
        {
            var tcs = new TaskCompletionSource<object>();
            var timer = new System.Timers.Timer(milliseconds) { AutoReset = false };
            timer.Elapsed += delegate { timer.Dispose(); tcs.SetResult(null); };
            timer.Start();
            return tcs.Task;
        }
    }　　

 

使用方法：

TaskEx.Run(() => MultiIssue());

TaskEx.Delay(10000);

　　

2. async  await

报错信息： 

Severity	Code	Description	Project	File	Line	Suppression State
Warning		The primary reference "Microsoft.Threading.Tasks" could not be resolved because it has an indirect dependency on the framework assembly "System.Runtime, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" which could not be resolved in the currently targeted framework. ".NETFramework,Version=v4.0". To resolve this problem, either remove the reference "Microsoft.Threading.Tasks" or retarget your application to a framework version which contains "System.Runtime, Version=1.5.11.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a".	DataconAutoIssue		

　　

App.config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    ....

	<runtime>
		<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
			<dependentAssembly>
				<assemblyIdentity name="System.Runtime" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
				<bindingRedirect oldVersion="0.0.0.0-2.6.8.0" newVersion="2.6.8.0" />
			</dependentAssembly>
			<dependentAssembly>
				<assemblyIdentity name="System.Threading.Tasks" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
				<bindingRedirect oldVersion="0.0.0.0-2.6.8.0" newVersion="2.6.8.0" />
			</dependentAssembly>
		</assemblyBinding>
	</runtime>
</configuration>　

 

引用DLL

 https://files.cnblogs.com/files/itstar/Task4.0DLLs.zip

 

3. public event EventHandler<string> ScannerMessageReceived;

报错信息：  

Severity	Code	Description	Project	File	Line	Suppression State
Error	CS0311	The type 'string' cannot be used as type parameter 'TEventArgs' in the generic type or method 'EventHandler<TEventArgs>'. There is no implicit reference conversion from 'string' to 'System.EventArgs'.	DataconAutoIssue	D:\project\E-info\DataconAutoIssue\ScannerTCP.cs	46	Active

　　

4.0写法：

public event Action<object, string> ScannerMessageReceived;