具有timeout 功能的函数调用

做项目的时候有时经常会需要一个带有timeout功能的函数调用。

比如从后台读数据并期望在给定时间内返回。借此机会包装了一个简单的C# class， 直接上代码吧.

public class TimeoutInvokerWrapper
        {
            private ManualResetEvent mTimeoutObject;
            private bool mBoTimeout;
            private Func<object, object> doHandler;

            public string Error { get; private set; }
            public object Result { get; private set; }

            public TimeoutInvokerWrapper(Func<object, object> handler)
            {
                this.doHandler = handler;
                this.mTimeoutObject = new ManualResetEvent(true);
            }

            public bool DoWithTimeout(object input, TimeSpan timeSpan)
            {
                if (this.doHandler == null)
                {
                    return false;
                }

                this.mTimeoutObject.Reset();
                this.mBoTimeout = true;

                this.doHandler.BeginInvoke(input, DoAsyncCallBack, null);
                if (!this.mTimeoutObject.WaitOne(timeSpan, false))
                {
                    this.mBoTimeout = true;
                }

                return this.mBoTimeout;
            }

            private void DoAsyncCallBack(IAsyncResult result)
            {
                try
                {
                    this.Result = this.doHandler.EndInvoke(result);
                    this.mBoTimeout = false;
                }
                catch (Exception ex)
                {
                    this.mBoTimeout = true;
                    this.Error = ex.ToString();
                }
                finally
                {
                    this.mTimeoutObject.Set();
                }
            }
        }

该类可以这样使用

public static void Main(string[] args)
        {
            Func<object, object> func = (obj) => { return obj.ToString(); };

            TimeoutInvokerWrapper wrapper = new TimeoutInvokerWrapper(func);
            bool isTimeout = wrapper.DoWithTimeout(123, TimeSpan.FromSeconds(2));
            if (isTimeout)
            {
                System.Console.WriteLine("function call timeout.");
            }
            else if (!string.IsNullOrEmpty(wrapper.Error))
            {
                System.Console.WriteLine("function call does not timeout but throw exception.");
            }
            else
            {
                System.Console.WriteLine("call succeed.")
                System.Console.WriteLine(wrapper.Result);   
            }
        }