Converting string to number

Question

It seems to be a very simple question, I use "0888" as my input value example here. I have researched for a while and tried different ways, such as

(int) "0888";
intval("0888");
floatval("0888");
settype("0888", "integer");

Unfortunately none of them seems to work. Reference 1 Reference 2 Reference 3

$num = $_POST['postcode'];

if((1000 <= $num && $num <= 1999) || (2000 <= $num && $num <= 2599) || (2619 <= $num && $num <= 2898) || (2921 <= $num && $num <= 2999)){
    $state = "NSW";
}
elseif((0200 <= $num && $num <= 0299) || (2600 <= $num && $num <= 2618) || (2900 <= $num && $num <= 2920)){
    $state = "ACT";
}
elseif((3000 <= $num && $num <= 3999) || (8000 <= $num && $num <= 8999)){
    $state = "VIC";
}
elseif((4000 <= $num && $num <= 4999) || (9000 <= $num && $num <= 9999)){
    $state = "QLD";
}
elseif((5000 <= $num && $num <= 5799) || (5800 <= $num && $num <= 5999)){
    $state = "SA";
}
elseif((6000 <= $num && $num <= 6797) || (6800 <= $num && $num <= 6999)){
    $state = "WA";
}
elseif((7000 <= $num && $num <= 7799) || (7800 <= $num && $num <= 7999)){
    $state = "TAS";
}
elseif((0800 <= $num && $num <= 0899) || (0900 <= $num && $num <= 0999)){
    $state = "NT";
}
else {
    $state = "Can not find this postcode record";
}

If I echo $stateI expect to see NT but actually I see "Can not find this postcode record" instead. Can anyone tell me what the problem is?

Most languages interpret strings starting with 0 as octal representations — flup, Sep 02 '13 at 05:57
Post codes are not numbers, especially if they hold a value that is not purely numeric, like a "leading 0". — deceze, Sep 02 '13 at 05:59
you need to add a bit more code, maybe you are assigning a variable wrongly — RozzA, Sep 02 '13 at 06:15

deceze · Accepted Answer · 2013-09-02T06:07:53.683

1

0299 is the octal notation of a number, which is very different from the decimal 299. In fact, 9 is invalid in octal and 0299 just has the value 2. Try echo 0299;, then echo 0123;.

If you're treating postcodes as numbers at all, you should strip leading 0s from it and don't use leading 0s in companions:

$code = ltrim($_POST['postcode'], '0');

... $code <= 299 ...

edited Sep 02 '13 at 06:07

answered Sep 02 '13 at 06:06

deceze

510,633
85
743
889

You said it, that is actually my problem, Thanks – Andrew Sep 02 '13 at 06:24

fedmich · Answer 2 · 2013-09-02T07:27:28.047

0

Use trim then ltrim for zeros, the second parameter allows using any characters you want to trim.

<?php
$num = $_POST['postcode'];
$num = ltrim( trim($_POST['postcode'], ' ') , '0'); //trim SPACES or ZERO

If you are sure the number comes in the left you can use ltrim(

// Just to be sure, finally reconvert it to (int)
$num = (int) $num;

edited Sep 02 '13 at 07:27

answered Sep 02 '13 at 06:23

fedmich

5,343
3
37
52

Actually you should try to trim on the right too, if this is from a POST/textboxes, sometimes user type in spaces, zeros. – fedmich Sep 02 '13 at 07:23
Actually you should try to trim spaces on the right too, if this is from a POST/textboxes, sometimes user type in spaces, zeros. When we examined a large db before, a lot of users had inserted spaces then, probably by mistake. – fedmich Sep 02 '13 at 07:25
1

If someone entered 9000 and you trimmed all the zeroes to the right it would then become 9 which is essentially 8991 less than 9000, how is that the same? – Hanky Panky Sep 02 '13 at 07:25

flup · Answer 3 · 2013-09-02T07:36:35.273

0

intval will by default parse your strings base 10 so $num = intval("0888"); will correctly parse the string to 888. No need to trim.

The integer literals in your if statements, however, get interpreted as octal numbers. Remove the leading zeros there:

[...] elseif((800 <= $num && $num <= 899)  [...]

edited Sep 02 '13 at 07:36

answered Sep 02 '13 at 07:06

flup

26,937
7
52
74

Converting string to number

3 Answers3