How to know if a custom indicator is available

[Yashar Seyyedin]

Hello everyone.

Indicator handles do not exist in metatrader4. So how do you make sure if indicator is available and iCustom is returning a valid number?

[Fabio Cavalloni]

If indicators do not exists you will see errors into Expert logs.

Then you can easily check the returned value for validity, value should be not 0, nor EMPTY_VALUE nor WRONG_VALUE, but it also depends on the used indicator and how was it coded...

[William Roeder]

ResetLastError, call iCustom, call GetLastError and see if the call failed.