Need to understand Difference MQL4 vs MQL5 iCustom function

 

MQL4 vs MQL5 iCustom function





Above image is from MQL4 documenation and lower is from MQL5. mode and shift parameter in MQL4 are missing but important. They are absent even in IndicatorCreate so I am confused as to how to handle supplying of mode and shift parameter.

 
MQL5 for Newbies: Guide to Using Technical Indicators in Expert Advisors
MQL5 for Newbies: Guide to Using Technical Indicators in Expert Advisors
  • www.mql5.com
In order to obtain values of a built-in or custom indicator in an Expert Advisor, first its handle should be created using the corresponding function. Examples in the article show how to use this or that technical indicator while creating your own programs. The article describes indicators that are built n the MQL5 language. It is intended for those who don't have much experience in the development of trading strategies and offers simple and clear ways of working with indicators using the offered library of functions.
 

MT4 gets a buffer value. MT5 returns a handle.

Perhaps you should read the manual, especially the examples.
   How To Ask Questions The Smart Way. (2004)
      How To Interpret Answers.
         RTFM and STFW: How To Tell You've Seriously Screwed Up.

They all (including iCustom) return a handle (an int). You get that in OnInit. In OnTick/OnCalculate (after the indicator has updated its buffers), you use the handle, shift and count to get the data.
          Technical Indicators - Reference on algorithmic/automated trading language for MetaTrader 5
          Timeseries and Indicators Access / CopyBuffer - Reference on algorithmic/automated trading language for MetaTrader 5
          How to start with MQL5 - General - MQL5 programming forum - Page 3 #22 (2020)
          How to start with MQL5 - MetaTrader 5 - General - MQL5 programming forum - Page 7 #61 (2020)
          How to call indicators in MQL5 - MQL5 Articles (2010)
          MQL5 for Newbies: Guide to Using Technical Indicators in Expert Advisors - MQL5 Articles (2010)

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