property Chart.IsNonworkingDate (Date as Variant, [Item as Variant]) as Boolean
Specifies whether the date is a nonworking day.

   Date as Variant A Date expression that indicates the date being queried.  
   Item as Variant A Long expression that indicates the handle of the item where the date-time is queried. For instance, the ItemNonWorkingUnits may specify a different non-working part for a particular item. If Item parameter is missing or 0, the default non-working part is used to determine whether specified date-time is a non-working or working unit. If the Item parameter is valid and the item displays a different non-working part using the ItemNonWorkingUnits property, the IsNonworkingDate property queries the Date using the item's non-working expression to determine whether it is a non-working unit.  
   Boolean A boolean expression that specifies whether the date is nonworking day.  
The IsNonworkingDate property specifies whether the giving date-time is a non-working or working unit in the chart. Use the ShowNonworkingUnits property to display or hide the non-working units as hours or days in your chart. Use the UnitWidthNonworking property to specify a different width for non-working units in the base level. Use the ShowNonworkingDates property to specify whether the the days are shown or hidden while the ShowNonworkingUnits property is False.

You can use the following functions to specify non-working parts in the chart:

You can use the following attributes for a bar ( ItemBar property ) to work with non-working part of the bars:

The following VB sample displays True if the cursor hovers a nonworking part, and False if the cursor hovers a working part in the chart area of the control:

Private Sub G2antt1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    With G2antt1
        Dim c As Long, hit As HitTestInfoEnum
        Debug.Print .Chart.IsNonworkingDate(.Chart.DateFromPoint(-1, -1), .ItemFromPoint(-1, -1, c, hit))
    End With
End Sub