PHP is_scalar() Function

The PHP is_scalar() function checks whether a variable is a scalar. The function returns true if the variable is a scalar, otherwise it returns false.

Scalar variables are those containing an int, float, string or bool. Types array, object and resource are not scalar. is_scalar() does not consider NULL to be scalar.

Syntax

is_scalar(variable)

Parameters

Return Value

Returns true if variable is a scalar, false otherwise.

Example:

The example below shows the usage of is_scalar() function.

<?php
var_dump(is_scalar(10));     //returns: bool(true)
var_dump(is_scalar(10.5));   //returns: bool(true)
var_dump(is_scalar(1e5));    //returns: bool(true)
var_dump(is_scalar('xyz'));  //returns: bool(true)
var_dump(is_scalar(true));   //returns: bool(true)

echo "\n";

var_dump(is_scalar(array()));   //returns: bool(false)
var_dump(is_scalar(null));      //returns: bool(false)
?>

The output of the above code will be:

bool(true)
bool(true)
bool(true)
bool(true)
bool(true)

bool(false)
bool(false)

Example:

Consider one more example where this function is used to check all elements of an array if they are a scalar or not.

<?php
$Arr = array(10, 10.5, null, false, 
             "xyz", 1e3, array()); 

foreach ($Arr as $value) {
  echo "is_scalar(".var_export($value, true).") = ";
  var_dump(is_scalar($value));
}
?>

The output of the above code will be:

is_scalar(10) = bool(true)
is_scalar(10.5) = bool(true)
is_scalar(NULL) = bool(false)
is_scalar(false) = bool(true)
is_scalar('xyz') = bool(true)
is_scalar(1000.0) = bool(true)
is_scalar(array (
)) = bool(false)