Excel export produces invalid Excel file with C1_* name

[ebruchez]

Finding the exact Excel name rules is challenging!

C1_FOO doesn't work, while B1_FOO does work. It appears that C and R are special.

There is also the R1C1 notation which should be watched for. This means using literally R and C, but then numbers, like R3C2. Brackets can be used for relative references, like R[-1]C3. The number is optional as in RC[1]!

+1 from customer

[ebruchez]

Work:

• C_FOO
• C.
• C_
• C1234567 (might depend on sheet size)
• B1R
• B1_FOO
• AA
• AA1_
• AA1FOO
• AAAA1 (might depend on sheet size)
• é
• é1

Don't work:

• C, c, R, r
• B1
• C1_FOO
• C123456
• AA1
• AAA1

Note that case doesn't matter.

We are leaning towards not prefixing all names, but prefixing the problematic names.

[ebruchez]

See also :

• https://contexturesblog.com/archives/2017/12/07/what-are-the-rules-for-excel-names/
• https://bettersolutions.com/excel/formulas/cell-references-a1-r1c1-notation.htm
• https://github.com/MartinTrummer/excel-names

[ebruchez]

Suggesting:

• use _ as prefix
• prefix with _ fields where suffix might need to be prefixed
• Form Builder should show these names