MQL5 File Handling for Creating and Writing a Trading Journal

Summary

This beginner-oriented article introduces MQL5 file operations through the first part of a trading-journal project. It explains how a script can use a file-selection dialog to let a trader choose an existing CSV file or enter a new filename, then open the file, write header information, and close it. The planned journal records account details and a chosen history period; a later installment is intended to export the trades themselves. The examples also explain dialog filters, default names, return values, and how file permissions affect whether a file can be created or updated.

The article’s practical contribution is a reusable workflow for user-selected storage rather than a fixed filename. It describes writing account name, balance, login, collection-period boundaries, and the last update time to make a journal easier to identify and interpret. The evidence consists of MQL5 examples and explanatory walkthroughs, not a tested trading strategy or performance study. This installment covers setup and basic writing; automated retrieval and export of historical trades are deferred to the next article, and the document does not compare file formats or address broader data-integrity concerns.

Key ideas

• A file dialog lets an MQL5 program use a user-selected file or create a new one.
• File filters and a default filename help guide selection of a journal file.
• The example writes account details, a history period, and an update timestamp as journal context.
• This installment establishes file selection and writing; trade-history export is deferred.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.