Which programming launguage can be used to buy/ sell FOREX currency pairs?

Question

How can I automatically buy or sell a currency pair (on a demo account), depending on whether a financial event is above or below it's forecast figure?

Obviously I know that many other factors affect the prices of currencies, but purely for the sake of learning, I would like to achieve this. I wanted to create a relatively simple algorithm but struggled to find any support.

Other relevant details / attempts to solve this:

• Previously attempted setting up buy or sell market orders before a high economic impact, so that as soon as the price moved significantly in a certain direction the position would automatically be opened. Downside of this is the position may be opened slightly too late.
• I will be closing the positions manually, once opened.
• The buy and sell tickets will already be set up on the platform screen, with the position sizes already pre-determined and entered in.
• Previously attempted waiting until the very second of a financial data release and clicking Buy / Sell (after planning for a few hours and finding potential relationships). This method is subject to human error, and is too slow.

Answer 1

_{Original text of this question was a bit different, about a year ago & this answer was accepted on:}

Can Auto Hot Keys be used to buy and/ sell FOREX currency pairs?

Yes, but production-grade solution will use other means for this

While AHK and other UI-layer scripting tools allow to auto-click/auto-fill things, such approach goes against the running river.

For decades the common FOREX trading terminals had it's own programming tools, that allow platform-integrated means for implementing this and similar ideas.

Yes, right - "snobby"-motivated nice-to-look-at "also"-Terminals, that rely just on web-GUI-layer ( not the webAPI, just the browser-based GUI-layer ), need not provide such a fully-fledged toolset, but frankly speaking, who would risk any AUM ( be it private or fund-operated ) on any such web-kit if it were not market-wide accepted for several years already, just for the sake of some nice, "contemporary"-looking UI? Sure, MARCOM & PR people strive to convince users to do this, but this is about risk & money, right?

Let's take an EasyLanguage, MQL4, C# languages as an example.

FOREX trading can use those tools, that are provided by your Broker, be it a:

• NinjaTrader's NinjaTrader with C# programming language
• TradeStation's TradeStation with EasyLanguage programming language
• MetaQuotes' MetaTrader Terminal 4 with MQL4 programming language
• MetaQuotes' MetaTrader Terminal 5 with MQL5 programming language

Having mentioned these few, the key concept is to realise that your idea has been on table for several decades and professional trading-desk automation has tried many ways to handle this.

Result?

The best what one can do in this dilemma is to spend some time with Broker-supported software IDE toolchains to get acquainted with relevant programming model(s) -- some concepts might be rather surprising on one's first look, but have rather long tradition in time-sensitive / resources-efficient code-execution systems design, so be courage-full to master the principles, as your professional knowledge will gain a lot from this expertise -- as an example, MetaTrader4 Terminal is one such software platform, that allows you to launch:

• 1x soloist Expert Advisor - as an event-driven code-execution algorithm per each MT4.Graph window
• Nx concurrent Custom Indicator-s event-driven restricted code-base per each MT4.Graph window
• 1x soloist Script asynchronous code-execution unit per each MT4.Graph* window

This inventory is quite important, as you have no other means how to automate complex Trading Algorithmisation but this ( sure, except the UI-layer automation, but which is blind with respect to all the trading-relevant contexts ( so quite pretty dangerous to take it seriously )).

Technical Indicators are executed under one common thread, which poses limitations for real-time robustness plus some restrictions apply for the permitted / forbidden operations that might be coded / compiled / executed in Indicator ( all aim at avoiding any and all possible blocking situations ( ref. solo-thread for all ... ) )

This said, you might have noticed, that both Expert Advisor and Technical Indicator-s are externally synchronised ( forget for the moment about a silicon-level details about non-parallel, shared thread execution with principal nanosecond scale of asynchronicity due to resource / code-execution scheduling ) and bound to externally issued anFxMarketEVENT in a form of an arriving signal ( once a price moves, MT4.Server sends QUOTE downstream message to the MT4.Terminal, a.k.a. a Tick ), which once ( if ) received, triggers MQL4 code-execution facilities on localhost:

• OnTick(){ ...} # in case of Expert Advisor
• OnCalculate(){...} # in case of Custom Technical Indicator

Why all this?

A good point -- well, FOREX is not an idyllic Eden, but rather a huge , fast & cruel Battlefield HELL. While the graphs paint on screen in silence, the Market roars as a never ending war between two immense-power forces evolves, nanosecond by nanosecond exchanging funds of more than about 5.300.000.000.000 USD value each day,
which is more than 615.000.000 USD / sec in average
and
your practical experience has already seen, what triple-hell chaos evolves, once Fundamental News appear to surprise the Titans who govern these mass-forces on the FOREX Markets.

This said, your code efforts shall rather use trading-platform integrated tools, than to rely on any externally emulated-fill&click proxies.

Nanoseconds do matter.

Do not hesitate to read more about algorithmic-trading and ask for more details.