PHP Regex - Value of 1 or more integers [duplicate] - php

Question

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php validate integer
(7 answers)
Closed 9 years ago.
Hey I'm trying to perform input validation in PHP to ensure that the stock values that are typed in are at least 1 positive integer and from 0-9. Should not contain any special characters.
For example, any of the following values should be valid:
7
0
32
47534
The following SHOULD NOT be valid:
asdf
35/gdf
../34.
etc..
I'm using the following if statement to check for the positive integer value of "$original_stock".
if (preg_match("/^[0-9]$/", $original_stock))
{
$error .="Original stock must be numerical.";
}
Additionally, I have a price field which should be validated as either an int or a double.
If there's an easier alternative to using regex, that's okay too!
Thanks in advance :)

Answer 1

Try this regexp:
/^\d+$/
The issue with your existing regexp is that it only matches strings with exactly one digit.
As for validating an int or a double:
/^\d+\.?\d*$/
Note that that regexp requires that there be at least one digit.

Answer 2

Use:
/^[0-9]+$/
The + means "one or more". Without it, your regex will only match a single digit. Or you could use the simpler variant:
/^\d+$/
For floats, try something like:
/^\d+(\.\d{1,2})?/
This will match one or more digits, optionally followed by a . and one or two digits. (i.e. .12 will not match.)
To save yourself some headaches, you can also use the is_int and is_float functions.
Lastly; note that your check is wrong. preg_match will return 0 if it fails, so you should write it as:
if (!preg_match("/^\+$/", $original_stock)) {
// error
}
(note the !).

Answer 3

You may want to use the
is_int

Answer 4

Don't reinvent a wheel slower than an existing one, use a motorcycle: is_int.
#Assuming $original_stock is a single value...
if (is_int($original_stock)) {
#Valid, do stuff
}
else {
#Invalid, do stuff
}
#Assuming $original_stock is an array...
$valid = true;
foreach ($original_stock as $s) {
if (!is_int($s)) {
$valid = false;
break;
}
}
if ($valid) {...}
else {...}

Answer 5

I just ran into this exact problem and solved it this way using the regex.
I think the problem is your caret ^.
/^[0-9]$/
I moved it inside the class and got the results I needed.
function validate_int($subject)
{
//Pattern is numbers
//if it matches anything but numbers, we want a fail
$pattern = '/[^0-9]/';
$matches = preg_match($pattern, $subject);
if($matches > 0)
return false;
else
return true;
}