如何在 PHP 中分隔数字并获取前两位数字？

Question

How can I separate a number and get the first two digits in PHP?

For example: 1345 -> I want this output=> 13 or 1542 I want 15 .

Answer 1

one possibility would be to use substr :

echo substr($mynumber, 0, 2);

EDIT:
please not that, like hakre said, this will break for negative numbers or small numbers with decimal places. his solution is the better one, as he's doing some checks to avoid this.

Answer 2

First of all you need to normalize your number, because not all numbers in PHP consist of digits only. You might be looking for an integer number:

$number = (int) $number;

Problems you can run in here is the range of integer numbers in PHP or rounding issues, see Integers ^Docs , INF comes to mind as well.

As the number now is an integer, you can use it in string context and extract the first two characters which will be the first two digits if the number is not negative. If the number is negative, the sign needs to be preserved:

$twoDigits = substr($number, 0, $number < 0 ? 3 : 2);

See the Demo .

Answer 3

Shouldn't be too hard? A simple substring should do the trick (you can treat numbers as strings in a loosely typed language like PHP).

See the PHP manual page for the substr() function.

Something like this:

$output = substr($input, 0, 2); //get first two characters (digits)

Answer 4

您可以获取数字的字符串值，然后使用substr获取您想要的部分。

Answer 5

this should do what you want

$length = 2;
$newstr = substr($string, $lenght);

Answer 6

With strong type-hinting in new version of PHP (> PHP 7.3) you can't use substr on a function if you have integer or float. Yes, you can cast as string but it's not a good solution. You can divide by some ten factor and recast to int.

$number = 1345; 
$mynumber = (int)($number/100);
echo $mynumber;

Display: 13

Answer 7

If you don't want to use substr you can divide your number by 10 until it has 2 digits:

<?php
function foo($i) {
    $i = abs((int)$i);
    while ($i > 99)
        $i = $i / 10;
    return $i;
}

will give you first two digits