Failed to open excel(.xlsx) with NPOI(2.5.6) with some specific graphs

[fjyuser]

Currently I'm trying to open the excel (workbook) which contain many sheets and each of the sheet contain multiple graphs.

Unfortunately, I cannot open the file and it throws error, but the error is empty string "" which is weird.

So what I tried is deleting the graph one by one, and then I can open the file.

It seems only 1 graph that cause the error, is there any specific graph that NPOI can handle and cannot handle?

May I know what cause this kind of behavior?

sample のコピー2.xlsx

[tonyqus]

How many graphs and sheets are there in this excel? Can you share the file?

[fjyuser]

Hi, it seems that only specific graph causes the error where I just attached the file. TQ

[tonyqus]

どうもありがとうございます

I can reproduce the issue.

[tonyqus]

The issue is caused by the following openxml block in chart1.xml

        <c:marker>
          <c:symbol val="auto"/>
        </c:marker>

The value 'auto' cannot be parsed (recognized) correctly.

[tonyqus]

It's weird that this value is not included in old definition of ST_MarkerStyle
https://c-rex.net/samples/ooxml/e1/Part4/OOXML_P4_DOCX_ST_MarkerStyle_topic_ID0ESVTRB.html

But I found it in Python-openxml lib

<xsd:simpleType name="ST_MarkerStyle">
<xsd:restriction base="xsd:string">
<xsd:enumeration value="circle"/>
<xsd:enumeration value="dash"/>
<xsd:enumeration value="diamond"/>
<xsd:enumeration value="dot"/>
<xsd:enumeration value="none"/>
<xsd:enumeration value="picture"/>
<xsd:enumeration value="plus"/>
<xsd:enumeration value="square"/>
<xsd:enumeration value="star"/>
<xsd:enumeration value="triangle"/>
<xsd:enumeration value="x"/>
<xsd:enumeration value="auto"/>
</xsd:restriction>
</xsd:simpleType>