//rest of the code
void OnStockTick(object sender, StockTick stockTick)
{
const decimal maxChangeRatio = 0.1m;
StockInfo stockInfo;
var quoteSymbol = stockTick.QuoteSymbol;
lock (_stockTickLocker)
{
var stockInfoExists = _stockInfos.TryGetValue(quoteSymbol, out stockInfo);
if (stockInfoExists)
{
var priceDiff = stockTick.Price - stockInfo.PrevPrice;
var changeRatio = Math.Abs(priceDiff / stockInfo.PrevPrice); //#A the percentage of change
if (changeRatio > maxChangeRatio)
{
Console.WriteLine("Stock:{0} has changed with {1} ratio, Old Price:{2} New Price:{3}", quoteSymbol,
changeRatio,
stockInfo.PrevPrice,
stockTick.Price);
}
_stockInfos[quoteSymbol].PrevPrice = stockTick.Price;
}
else
{
_stockInfos[quoteSymbol] = new StockInfo(quoteSymbol, stockTick.Price);
}
}
}