DoWhile.cs

/// <summary>
/// Loop until a condition is met and your function returns true
/// </summary>
/// <param name="action">The delegate to run. Return true to exit the loop.</param>
/// <param name="delay">Return a timespan for the delay between loops</param>
/// <param name="whentoStop">Return true when the loop should stop when catching exceptions or looping</param>
public static void DoUntil(Func<bool> action, Func<int, TimeSpan, TimeSpan> delay, Func<int, TimeSpan, bool> whentoStop)
{
    var startedUtc = DateTime.UtcNow;
    var amountOfRetriesAllowed = 0;
    while (true)
    {
        try
        {
            if (action()) return;
        }
        catch
        {
            if (whentoStop(amountOfRetriesAllowed, DateTime.UtcNow.Subtract(startedUtc))) throw;
        }
        finally
        {
            amountOfRetriesAllowed++;
        }

        var calculatedDelay = delay(amountOfRetriesAllowed, DateTime.UtcNow.Subtract(startedUtc));
        if (calculatedDelay.TotalMilliseconds < 0)
        {
            calculatedDelay = TimeSpan.Zero;
        }
        Thread.Sleep(calculatedDelay);
    }
}

Example:

DoUntil(() => worker.DoesSomethingAndReturnsTrue(), (i, t) => TimeSpan.Zero, (i, t) => i < 100);