How we can change currency format to decimal format for use calculate in php

Hi, you may consider using the following code.
As PHP derives heavily from C, it has a number of functions and behaviours that are similar/identical.

One function of use is sscanf, which allows you to scan a string for particular types of data. You can grab strings, numbers and characters for instance. In my understanding, neither C nor PHP's sscanf function were designed to use decimal separators other than a period. Also,they're not designed for use with thousands-separators either.

With this in mind, we can go about transforming the string into something that sscanf will handle. We can then grab it as a floating-point number and perform mathematical operations on it. We can then finally convert this number back into a string representation, even being able to specify which character is used for both types of separator.

<?php
    $inputStr = '34.000.000,23';
    echo $inputStr . '<br>';

    // turn the string into a format sscanf will work with.
    // this involves removing the thousands-separators  and making the decimal separators  a period (.)
    $numberStr = str_replace('.', '', $inputStr);
    $numberStr = str_replace(',', '.', $numberStr);

    //now get the string of a number into an actual number we can do calculations with.
    sscanf($numberStr, '%f', $number);

    //double the number
    $number *= 2;

    // make a string of this value, with 2 places after the decimal point, using (,) as the decimal seperator,
    // and (.) as the thousands separators
    $outputStr = number_format($number, 2, ',', '.');


    echo $outputStr . "<br>";
?>

Output

34.000.000,23
68.000.000,46