[Code Monkey]

That will die on spaces. This should work.

PHP Code:

$test_one = '1 23465';

if(preg_match('#[^0-9\s]#',$test_one))
{
    $result = 'Ahah! Found an evil character.';
}
else
{
    $result = 'Only Digits and Spaces here!';
}

echo $result; 


You you need to check multiple items use it as a function.

PHP Code:

$test_one = '1 23465';

if(digitsOnly($test_one))
{
    $result = 'Ahah! Found an evil character.';
}
else
{
    $result = 'Only Digits and Spaces here!';
}

echo $result;

function digitsOnly($target)
{
    return preg_match('#[^0-9\s]#', $target);
}