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columnHeaderFormat 3.8.0

Determines the text that will be displayed on the calendar’s column headings.

format string, default:

'ddd'     // like 'Mon', for month view
'ddd M/D' // like 'Mon 9/7', for week views
'dddd'    // like 'Monday', for day views

As noted above, each view has a specific default. Get fine-tuned control with View-Specific Options. A single string alone will set the value for all views.

The default values will change based on the current locale.

If you need programmatic control, use columnHeaderText or columnHeaderHtml instead.

This setting was renamed from columnFormat in version 3.8.0