改進的number_format（）函數可用於大於2^53的數字

Question

我創建了一個輸出數據的API，用於GET請求。此數據也根據用戶的區域設置進行格式化。我使用了PHP number_format()函數，並注意到對於大於2^53的數字，數字格式輸出不同的數字（它近似於它們）。這是一個問題，所以我不得不創建一個克服這個問題的函數。 請看例子，以瞭解這個問題：

$original_number = 9223372036854775805.123; 
echo a_number_format($original_number, 4, ".", "'",3); 
echo "<br />"; 
echo number_format($original_number, 4, ".", "'"); 
// Outputs: 
9'223'372'036'854'775'805.1230 
9'223'372'036'854'775'808.0000 
// Please note that number_format() returns aproximate value for any number bigger than 2^53 

Answer 1

function number_format($number_in_iso_format, $no_of_decimals=3, $decimals_separator='.', $thousands_separator='', $digits_grouping=3){ 
    // Check input variables 
    if (!is_numeric($number_in_iso_format)){ 
     error_log("Warning! Wrong parameter type supplied in my_number_format() function. Parameter \$number_in_iso_format is not a number."); 
     return false; 
    } 
    if (!is_numeric($no_of_decimals)){ 
     error_log("Warning! Wrong parameter type supplied in my_number_format() function. Parameter \$no_of_decimals is not a number."); 
     return false; 
    } 
    if (!is_numeric($digits_grouping)){ 
     error_log("Warning! Wrong parameter type supplied in my_number_format() function. Parameter \$digits_grouping is not a number."); 
     return false; 
    } 


    // Prepare variables 
    $no_of_decimals = $no_of_decimals * 1; 


    // Explode the string received after DOT sign (this is the ISO separator of decimals) 
    $aux = explode(".", $number_in_iso_format); 
    // Extract decimal and integer parts 
    $integer_part = $aux[0]; 
    $decimal_part = isset($aux[1]) ? $aux[1] : ''; 


    // Extract the negative sign 
    $sign=''; 
    if (strpos($integer_part,"-")===0){ 
     $sign = '-'; 
     $integer_part = substr($integer_part,1); 
    } 



    // Adjust decimal part (increase it, or minimize it) 
    if ($no_of_decimals > 0){ 
     // Check actual size of decimal_part 
     // If its length is smaller than number of decimals, add trailing zeros, otherwise round it 
     if (strlen($decimal_part) < $no_of_decimals){ 
      $decimal_part = str_pad($decimal_part, $no_of_decimals, "0"); 
     } else { 
      $decimal_part = substr($decimal_part, 0, $no_of_decimals); 
     } 
    } else { 
     // Completely eliminate the decimals, if there $no_of_decimals is a negative number 
     $decimals_separator = ''; 
     $decimal_part  = ''; 
    } 

    // Format the integer part (digits grouping) 
    if ($digits_grouping > 0){ 
     $aux = strrev($integer_part); 
     $integer_part = ''; 
     for ($i=strlen($aux)-1; $i >= 0 ; $i--){ 
      if ($i % $digits_grouping == 0 && $i != 0){ 
       $integer_part .= "{$aux[$i]}{$thousands_separator}"; 
      } else { 
       $integer_part .= $aux[$i];   
      } 
     } 
    } 

    $processed_number = "{$sign}{$integer_part}{$decimals_separator}{$decimal_part}"; 
    return $processed_number; 
}