php 取小数点后面几位

sdchy

string number_format ( float $number [, int $decimals ] )
string number_format ( float $number , int $decimals , string $dec_point , string $thousands_sep )
decimals :小数点后面2位
dec_point ：小数点用什么符号
thousands_sep：每隔3位时用什么符号
eg:
<?php
$number = 1234.56;
// english notation (default)
$english_format_number = number_format($number);
// 1,235
// French notation
$nombre_format_francais = number_format($number, 2, ',', ' ');
// 1 234,56
$number = 1234.5678;
// english notation without thousands seperator
$english_format_number = number_format($number, 2, '.', '');
// 1234.57
?>