Here's a list of Metatrader 4 symbols you can use to change the default appearance of "buy" and "sell" arrows drawn on your charts by your expert advisors or indicators.
MT4 Symbol Table
How it works (example)?
Original Code
SetIndexArrow(1, 234); //Arrow down symbol
SetIndexArrow(0, 233); //Arrow up symbol
Just modify the code to whatever you want and decompile the MT4 source code. For example, if you like to display arrow code 221 and 222, you need to write:
Modified Code
SetIndexArrow(1, 222); //Arrow down symbol
SetIndexArrow(0, 221); //Arrow up symbol
Then decompile and you're done.
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