Re: [PHP] variable type - conversion/checking

On 15/03/13 06:21, Jim Lucas wrote:
> On 3/14/2013 4:05 PM, Matijn Woudt wrote:
>> On Thu, Mar 14, 2013 at 11:44 PM, Jim Lucas <[email protected]> wrote:
>>
>>> On 03/14/2013 11:50 AM, Samuel Lopes Grigolato wrote:
>>>
>>>> Something like "if (is_numeric($var)&& $var == floor($var))" will do
>>>> the
>>>>
>>>> trick. I don't know if there's a better (more elegant) way.
>>>>
>>>>
>>>> On Thu, Mar 14, 2013 at 3:09 PM, Matijn Woudt<[email protected]> wrote:
>>>>
>>>> On Thu, Mar 14, 2013 at 7:02 PM, georg<[email protected]**>
>>>>> wrote:
>>>>>
>>>>> Hi,
>>>>>>
>>>>>> I have tried to find a way to check if a character string is
>>>>>> possible to
>>>>>> test whether it is convertible to an intger !
>>>>>>
>>>>>> any suggestion ?
>>>>>>
>>>>>> BR georg
>>>>>>
>>>>>
>>>>>
>>>>> You could use is_numeric for that, though it also accepts floats.
>>>>>
>>>>> - Matijn
>>>>>
>>>>>
>>>>
>>> for that type of test I have always used this:
>>>
>>> if ( $val == (int)$val ) {
>>>
>>> http://www.php.net/manual/en/**language.types.integer.php#**
>>> language.types.integer.casting<http://www.php.net/manual/en/language.types.integer.php#language.types.integer.casting>
>>>
>>>
>>>
>> I hope you're not serious about this...
>>
>> When comparing a string and an int, PHP will translate the string to int
>> too, and of course they will always be equal then.
>> So:
>> $a = "abc";
>> if($a == (int)$a) echo "YES";
>> else echo "NO";
>> Will always return YES.
>>
>> - Matijn
>>
>
> Hmmmm... Interesting. Looking back at my code base where I thought I was
> doing that, turns out the final results were not that, but this:
>
> $value = "asdf1234";
>
> if ( $value === (string)intval($value) ) {
>
> Looking back at the OP's request and after a little further searching,
> it seems that there might be a better possible solution for what the OP
> is requesting.
>
> <?php
>
> $values = array("asdf1234", "123.123", "123");
>
> foreach ( $values AS $value ) {
>
> echo $value;
>
> if ( ctype_digit($value) ) {
> echo ' - is all digits';
> } else {
> echo ' - is NOT all digits';
> }
> echo '<br />'.PHP_EOL;
> }
>
> returns...
>
> asdf1234 - is NOT all digits
> 123.123 - is NOT all digits
> 123 - is all digits
>
> http://www.php.net/manual/en/function.ctype-digit.php
>
> An important note:
>
> This function expects a string to be useful, so for example passing in
> an integer may not return the expected result. However, also note that
> HTML forms will result in numeric strings and not integers. See also the
> types section of the manual.
>
> --
> Jim
>

Integers can be negative too: I suspect your test would reject a leading '-'...


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