Tutorial 145 | Using Streamwriter & Streamreader to store and read bid/ask data

Tutorial 145 demonstrates how to retain historical data by storing information in a text file, using Streamwriter. When the chart is reloaded the program then checks each bar to see if there is data available in the text file for that bar using Streamreader and a Dictionary. If data is available for a bar, it is retrieved is available for use. For real time bars arriving the real time data can be used and displayed, but it is also stored in the text file, for possible future use.

See https://markplex.com/free-tutorials/tutorial-145-using-streamwriter-streamreader-to-store-and-read-bid-ask-data/ for more details.