PHPOffice/PhpSpreadsheet · error · PhpOffice\PhpSpreadsheet\Exception

Cell coordinate can not be zero-length string.

Error message

Cell coordinate can not be zero-length string.

What it means

removeComment() rejects coordinates that are empty after sheet-prefix trimming. An empty string can neither address an existing comment nor serve as a storage key, so removeComment('') (or 'Sheet1!', which Functions::trimSheetFromCellReference() reduces to '') throws before the comments map is consulted.

Source

Thrown at src/PhpSpreadsheet/Worksheet/Worksheet.php:2975

    /**
     * Remove comment from cell.
     *
     * @param array{0: int, 1: int}|CellAddress|string $cellCoordinate Coordinate of the cell as a string, eg: 'C5';
     *               or as an array of [$columnIndex, $row] (e.g. [3, 5]), or a CellAddress object.
     *
     * @return $this
     */
    public function removeComment(CellAddress|string|array $cellCoordinate): self
    {
        $cellAddress = Functions::trimSheetFromCellReference(Validations::validateCellAddress($cellCoordinate));

        if (Coordinate::coordinateIsRange($cellAddress)) {
            throw new Exception('Cell coordinate string can not be a range of cells.');
        } elseif (str_contains($cellAddress, '$')) {
            throw new Exception('Cell coordinate string must not be absolute.');
        } elseif ($cellAddress == '') {
            throw new Exception('Cell coordinate can not be zero-length string.');
        }
        // Check if we have a comment for this cell and delete it
        if (isset($this->comments[$cellAddress])) {
            unset($this->comments[$cellAddress]);
        }

        return $this;
    }

    /**
     * Get comment for cell.
     *
     * @param array{0: int, 1: int}|CellAddress|string $cellCoordinate Coordinate of the cell as a string, eg: 'C5';
     *               or as an array of [$columnIndex, $row] (e.g. [3, 5]), or a CellAddress object.
     */
    public function getComment(CellAddress|string|array $cellCoordinate, bool $attachNew = true): Comment
    {
        $cellAddress = Functions::trimSheetFromCellReference(Validations::validateCellAddress($cellCoordinate));

View on GitHub (pinned to 65b080eef4)

Solutions

1. Guard for empty strings before calling and skip blank entries.
2. When concatenating sheet-prefixed refs, validate the cell part is non-empty.
3. Default missing config to a real coordinate or branch around the call.

Example fix

// before
$sheet->removeComment($headers['note_col'] ?? ''); // '' when key missing -> throws

// after
$noteCol = $headers['note_col'] ?? null;
if (is_string($noteCol) && $noteCol !== '') {
    $sheet->removeComment($noteCol);
}

if ($coord === null || $coord === '' || str_ends_with($coord, '!')) {
    // no usable cell address: skip
} else {
    $sheet->removeComment($coord);
}

/** Empty strings and bare sheet prefixes ('Sheet1!') are not cells. */
function isNonEmptyCoordinate(?string $address): bool
{
    return is_string($address) && $address !== '' && !str_ends_with($address, '!');
}

When it happens

Trigger: removeComment(''); removeComment('Summary!') where only the sheet prefix was present; coordinates built from missing array keys or null variables stringified to ''.

Common situations: Iterating header maps or user-supplied column lists where some keys are absent; dynamic code that assembles coordinates from possibly-empty variables.

Related errors

• Cell coordinate string must not be absolute.
• Column is not within the table range.
• Freeze pane can not be set on a range of cells.
• Rows can only be inserted before at least row 1.
• Column references should not be numeric.

AI-assisted analysis of PHPOffice/PhpSpreadsheet@65b080eef4 (2026-08-17). Data as JSON: /api/errors/cfcd80aa69aef03a. Report an issue: GitHub.