Implementing RegEx Timeout in .NET 4

Question

Platform: Silverlight 4, .NET 4

With the .NET 4.5 Developer preview the RegEx class has been enhanced to allow setting of a Timeout value which would prevent the Reg

Answer 1

I re-implemented the above code changing it in a way that I belive is more reliable.

    /// 

    /// Executes function proc on a separate thread respecting the given timeout value.
    /// 
    /// 
    /// The function to execute.
    /// The timeout duration.
    /// 
    public static R ExecuteWithTimeout(Func proc, TimeSpan timeout) {
        var r = default(R); // init default return value
        Exception ex = null; // records inter-thread exception

        // define a thread to wrap 'proc'
        var t = new Thread(() => {
            try {
                r = proc();
                }
            catch (Exception e) {
                // this can get set to ThreadAbortException
                ex = e;

                Debug.WriteLine("Exception hit");

                }
            });

        t.Start(); // start running 'proc' thread wrapper
        // from docs: "The Start method does not return until the new thread has started running."

        if (t.Join(timeout) == false) {
            t.Abort(); // die evil thread!
            // Abort raises the ThreadAbortException
            int i = 0;
            while ((t.Join(1) == false) && (i < 20)) { // 20 ms wait possible here
                i++;
                }
            if (i >= 20) {
                // we didn't abort, might want to log this or take some other action
                // this can happen if you are doing something indefinitely hinky in a
                // finally block (cause the finally be will executed before the Abort 
                // completes.
                Debug.WriteLine("Abort didn't work as expected");
                }
            }

        if (ex != null) {
            throw ex; // oops
            }
        return r; // ah!
        }