Software Developer's Kit - ChemDraw

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HeadCenterSize Property
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Member of ChemDraw Control.Spline.

Sets and returns the distance from the start of spline arrow head to the center of the spline arrow head. 

Property type

Read-write property


Visual Basic
Public Property HeadCenterSize() As Double

Return Type



Increasing head center value will increase the distance from start of the arrow head to the center of the arrow head.    

Arrow A   

Arrow B

In Arrow B the head center size has decreased slightly. The arrow head remains unchanged, except for the center point which has moved nearer to the start of the arrow.
An arrow with the same value for head size and head center size will look like this arrow
(the end of arrow head is at 90° from the arrow line)

The value for head center size is expressed in points.  


'Declares variable vSpline
 Dim vSpline As ChemDrawControl10Ctl.Spline
'Checks that there is a Spline loaded in the variable

 If  Selection.Splines.Count < 1 Then
     Exit Sub
 End If

 Private Sub ctlChemDraw_SelectionChanged(ByVal selection As ChemDrawControl10Ctl.IChemDrawSelection)
     If  selection.Splines.Count = 1 Then
         Set MySpline = ctlChemDraw.selection.Objects.Splines.Item(1)
         Label1.Caption = "Object: Spline"
     End If
 End Sub
 Private Sub cmdHeadCenterSize_click()
    'Returns and sets a number as a value for head center size 
     vSpline.HeadCenterSize = Val(txtLoad.Text)

Text1.text = vSpline.HeadCenterSize
 End Sub

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