圆形函数php

Question

Maybe the question is simple, but I can't find the answer. What I need to do is to round number to 2 places after comma. Im using this:

round(($data/$count*100), 2)

And when I get number like:

60.36036036036012 and : 37.83783783783808 is OK, because it's: 60.36 and 37.84

But why this:

1.8018018018018036

Is rounded to this:

1.8000000000000003 

How to round always to 2 places, after comma?

Answer 1

You should get 1.8 unless you use something like old PHP version with some sort of related bugs. Still, if you want to see 1.80 you need to format output string, otherwise trailing zero will be stripped by default. The most flexible approach would be to use sprintf() formatting, like this:

$val = 1.8000000000000003;
printf("%.02f", round( $val, 2 ));

which would produce

1.80

The key is "%.02f" which means you want to format (f)loating point value, with two digits after dot, padded with 0 when needed (like this case).

See the sprintf() docs for more about available formatting possibilites.

Answer 2

使用 PHP NumberFormatter 类http://es.php.net/manual/es/class.numberformatter.php