How to get the bar number/time from OnChartEvent()?

[Rasoul Mojtahedzadeh]

In an Expert Advisor code, I would like to know on which bar of a chart the user clicked. From the example and documentation of OnChartEvent() function, a left click of mouse can be captured as a position (x, y). Is there a way to get the bar time/number on which the user left clicked?

[Keith Watford]

ChartXYToTimePrice

then

iBarShift 

[Rasoul Mojtahedzadeh]

GumRai:

ChartXYToTimePrice

then

iBarShift 

Thanks!