Undefined offset in Xlsx reader

[nick-lai]

This is:

- [*] a bug report
- [ ] a feature request
- [ ] **not** a usage question (ask them on https://stackoverflow.com/questions/tagged/phpspreadsheet or https://gitter.im/PHPOffice/PhpSpreadsheet)

Which versions of PhpSpreadsheet and PHP are affected?

php: ^7.0

PHPOffice/PhpSpreadsheet: ^1.8.2

File: Undefined offset in Xlsx reader(Cell B1 is an empty richtext).xlsx

PhpSpreadsheet/src/PhpSpreadsheet/Reader/Xlsx.php

Lines 439 to 447 in 9fab890

	if (isset($xmlStrings, $xmlStrings->si)) {
	foreach ($xmlStrings->si as $val) {
	if (isset($val->t)) {
	$sharedStrings[] = StringHelper::controlCharacterOOXML2PHP((string) $val->t);
	} elseif (isset($val->r)) {
	$sharedStrings[] = $this->parseRichText($val);
	}
	}
	}

The processing of 441 to 445 lines causes the $sharedStrings array to skip the empty SimpleXMLElement object.

Example for $xmlStrings:

SimpleXMLElement::__set_state(array(
    // '@attributes' => ...
    'si' =>
    array (
        0 => SimpleXMLElement::__set_state(array(
           't' => 'Name',
        )),
        1 => SimpleXMLElement::__set_state(array()), // will be skipped.
        // ...
    )
))

PhpSpreadsheet/src/PhpSpreadsheet/Reader/Xlsx.php

Lines 675 to 688 in 9fab890

	// Read cell!
	switch ($cellDataType) {
	case 's':
	if ((string) $c->v != '') {
	$value = $sharedStrings[(int) ($c->v)];
	if ($value instanceof RichText) {
	$value = clone $value;
	}
	} else {
	$value = '';
	}
	break;

In this case, a undefined offset error would occur on line 679.

Fix for empty SimpleXMLElement:

foreach ($xmlStrings->si as $val) {
    if (isset($val->t)) {
        $sharedStrings[] = StringHelper::controlCharacterOOXML2PHP((string) $val->t);
    } elseif (isset($val->r)) {
        $sharedStrings[] = $this->parseRichText($val);
    } else {
        // When SimpleXMLElement is empty the `t` and `r` properties no exists.
        $sharedStrings[] = ''; 
    }
}

[nick-lai]

@MarkBaker

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.
If this is still an issue for you, please try to help by debugging it further and sharing your results.
Thank you for your contributions.

[oleibman]

Reopening, (very late) fix is on the way.