Php check if string is float or int

Artefacto's answer will also convert a 5.0 float number into a 5 integer. If that is bugging you like it was bugging me, I offer the answer of automatic type conversion via the multiplication operator:

If either operand is a float, then both operands are evaluated as floats, and the result will be a float. Otherwise, the operands will be interpreted as ints, and the result will also be an int.

$demo = array[
    1, 2, 3, '1', '2', '3', 
    1.0, 2.1, 3.2, '1.0', '2.1', '3.2', 
    -17, '-17', 
    -1.0, -2.2, '-1.0', '-2.2',
    0, '0', -0, '-0',
    0.0, '0.0', -0.0, '-0.0',
];

foreach [$demo as $k => $v] {
    if [is_numeric[$v] && is_string[$v]] {
        $demo[$k] = 1 * $v;
    }
}

echo "
"; var_dump[$demo]; echo "
";

array[26] {
  [0]=>
  int[1]
  [1]=>
  int[2]
  [2]=>
  int[3]
  [3]=>
  int[1]
  [4]=>
  int[2]
  [5]=>
  int[3]
  [6]=>
  float[1]
  [7]=>
  float[2.1]
  [8]=>
  float[3.2]
  [9]=>
  float[1]
  [10]=>
  float[2.1]
  [11]=>
  float[3.2]
  [12]=>
  int[-17]
  [13]=>
  int[-17]
  [14]=>
  float[-1]
  [15]=>
  float[-2.2]
  [16]=>
  float[-1]
  [17]=>
  float[-2.2]
  [18]=>
  int[0]
  [19]=>
  int[0]
  [20]=>
  int[0]
  [21]=>
  int[0]
  [22]=>
  float[0]
  [23]=>
  float[0]
  [24]=>
  float[-0]
  [25]=>
  float[-0]
}

I am trying to check in php if a string is a double or not.

Here is my code:

   if[floatval[$num]]{
         $this->print_half_star[];
    }

$num is a string..The problem is that even when there is an int it gives true. Is there a way to check if it is a float and not an int!?

asked Aug 7, 2012 at 15:54

1

// Try to convert the string to a float
$floatVal = floatval[$num];
// If the parsing succeeded and the value is not equivalent to an int
if[$floatVal && intval[$floatVal] != $floatVal]
{
    // $num is a float
}

answered Aug 7, 2012 at 16:02

4

This will omit integer values represented as strings:

if[is_numeric[$num] && strpos[$num, "."] !== false]
{
    $this->print_half_star[];
}

answered Aug 7, 2012 at 16:01

JK.JK.

5,0861 gold badge26 silver badges26 bronze badges

1

You can try this:

function isfloat[$num] {
    return is_float[$num] || is_numeric[$num] && [[float] $num != [int] $num];
}

var_dump[isfloat[10]];     // bool[false]
var_dump[isfloat[10.5]];   // bool[true]
var_dump[isfloat["10"]];   // bool[false]
var_dump[isfloat["10.5"]]; // bool[true]

answered Aug 7, 2012 at 16:02

FlorentFlorent

12.3k10 gold badges46 silver badges58 bronze badges

1

You could just check if the value is numeric, and then check for a decimal point, so...

if[is_numeric[$val] && stripos[$val,'.'] !== false]
{
    //definitely a float
}

It doesn't handle scientific notation very well though, so you may have to handle that manually by looking for e

answered Nov 28, 2018 at 19:27

Why not use the magic of regular expression