How to get the number of columns of worksheet as integer (28) instead of Excel-letters (“AB”)?

Question

Given:

$this->objPHPExcelReader = PHPExcel_IOFactory::createReaderForFile($this->config[\'file\']);
$this->objPHPExcelReader->setLoadSheetsOnly(a         


        

Answer 1

This is a somewhat simplified version of dqhendricks answer. I have added to copies, one function assuming you enter the full excel cell reference (ie. "AB12") and the other assuming you enter just the column reference (ie. "AB"). They both return a zero based index.

Input Full Cell Reference

function getIndex ($cell) {
    // Strip cell reference down to just letters
    $let = preg_replace('/[^A-Z]/', '', $cell);

    // Iterate through each letter, starting at the back to increment the value
    for ($num = 0, $i = 0; $let != ''; $let = substr($let, 0, -1), $i++)
        $num += (ord(substr($let, -1)) - 65) * pow(26, $i);

    return $num;
}

Input Column Reference Only

function getIndex ($let) {
    // Iterate through each letter, starting at the back to increment the value
    for ($num = 0, $i = 0; $let != ''; $let = substr($let, 0, -1), $i++)
        $num += (ord(substr($let, -1)) - 65) * pow(26, $i);

    return $num;
}

The function goes from the back of the string to the front to increase the value of the column. It uses the ord() function to get the numeric value of a character and then has the letter value subtracted to give the local column value. Finally it is multiplied by the current power of 26.