c# run thread in threadpool

This is the way of running thread in ThreadPool
1 only for 4.5 Framework

Task.Run(() => doStuff("hello world"));

2

Task.Factory.StartNew(() => doStuff("hello world"));

3

ThreadPool.QueueUserWorkItem(a => doStuff("hello world"));

4

void Example()
{
    // Hook up the ProcessFile method to the ThreadPool.
    // Note: 'a' is an argument name. Read more on arguments.
    ThreadPool.QueueUserWorkItem(new WaitCallback(ProcessFile), a);
}

private void ProcessFile(object a)
{
    // I was hooked up to the ThreadPool by WaitCallback.
}

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