Hi all,

I am trying to chart data that contains null values, I want the null
values to be represented as a gap or such.
The chart series are dynamically created from code using a series
formula.
The chart needs to be editable as well as the underlying data.

My attempts at displaying null data is slowly painting me into a corner.

Issue 1:
The series formula will not allow null values to be included in the
selected cells. Any attempt to include a null value in the series range will
give me a COMException.

Workaround 1:
Bind the series to an area on the sheet filled with formulas like
IF(ISBLANK(D3),NA(),D3)
This allows me to display the chart and dynamically change range of
values being displayed. Yay. NA() = graphical null value!?

Issue 2:
Editng the chart now invokes the goal seek helper requesting that I
specify the cell to change.
This renders the chart editing functionality useless because now a value
needs to be entered to allow the goal seek to perform and change the
underlying value.

Questions
Can I somehow display null values in the chart without compomising the
editing behaviour?
Can I override the GOAL SEEK behaviour?


I am developing an excel solution using VSTO 2003 and C#.

Thanks in advance

Mark Sargent