Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Worksheet/Worksheet.php
public function cellExists($pCoordinate)
    {
        // Worksheet reference?
        if (strpos($pCoordinate, '!') !== false) {
            $worksheetReference = self::extractSheetTitle($pCoordinate, true);

            return $this->parent->getSheetByName($worksheetReference[0])->cellExists(strtoupper($worksheetReference[1]));
        }

        // Named range?
        if ((!preg_match('/^' . Calculation::CALCULATION_REGEXP_CELLREF . '$/i', $pCoordinate, $matches)) &&
            (preg_match('/^' . Calculation::CALCULATION_REGEXP_NAMEDRANGE . '$/i', $pCoordinate, $matches))) {
            $namedRange = NamedRange::resolveRange($pCoordinate, $this);
            if ($namedRange !== null) {
                $pCoordinate = $namedRange->getRange();
                if ($this->getHashCode() != $namedRange->getWorksheet()->getHashCode()) {
                    if (!$namedRange->getLocalOnly()) {
                        return $namedRange->getWorksheet()->cellExists($pCoordinate);
                    }

                    throw new Exception('Named range ' . $namedRange->getName() . ' is not accessible from within sheet ' . $this->getTitle());
                }
            } else {
                return false;
            }
        }

        // Uppercase coordinate
        $pCoordinate = strtoupper($pCoordinate);

        if (Coordinate::coordinateIsRange($pCoordinate)) {
            throw new Exception('Cell coordinate can not be a range of cells.');
        } elseif (strpos($pCoordinate, '$') !== false) {
            throw new Exception('Cell coordinate must not be absolute.');
        }

        // Cell exists?
        return $this->cellCollection->has($pCoordinate);
    }
public function cellExists($pCoordinate)
    {
        // Worksheet reference?
        if (strpos($pCoordinate, '!') !== false) {
            $worksheetReference = self::extractSheetTitle($pCoordinate, true);

            return $this->parent->getSheetByName($worksheetReference[0])->cellExists(strtoupper($worksheetReference[1]));
        }

        // Named range?
        if ((!preg_match('/^' . Calculation::CALCULATION_REGEXP_CELLREF . '$/i', $pCoordinate, $matches)) &&
            (preg_match('/^' . Calculation::CALCULATION_REGEXP_NAMEDRANGE . '$/i', $pCoordinate, $matches))) {
            $namedRange = NamedRange::resolveRange($pCoordinate, $this);
            if ($namedRange !== null) {
                $pCoordinate = $namedRange->getRange();
                if ($this->getHashCode() != $namedRange->getWorksheet()->getHashCode()) {
                    if (!$namedRange->getLocalOnly()) {
                        return $namedRange->getWorksheet()->cellExists($pCoordinate);
                    }

                    throw new Exception('Named range ' . $namedRange->getName() . ' is not accessible from within sheet ' . $this->getTitle());
                }
            } else {
                return false;
            }
        }

        // Uppercase coordinate
        $pCoordinate = strtoupper($pCoordinate);

        if (Coordinate::coordinateIsRange($pCoordinate)) {
            throw new Exception('Cell coordinate can not be a range of cells.');
        } elseif (strpos($pCoordinate, '$') !== false) {
            throw new Exception('Cell coordinate must not be absolute.');
        }

        // Cell exists?
        return $this->cellCollection->has($pCoordinate);
    }
Does the cell at a specific coordinate exist?

@param string $pCoordinate Coordinate of the cell eg: 'A1'

@throws Exception

@return bool