Master PHP’s is_int(): Quick Guide with Real Code Examples

PHP is a widely used scripting language for web development, offering many built‑in functions. One useful function is is_int(), which checks whether a variable is an integer, helping developers quickly determine a variable’s type.

The syntax of is_int() is: bool is_int ( mixed $var ) The function accepts a single parameter $var of any type and returns true if the variable is an integer, otherwise false.

Example 1

<?php
$num1 = 10; // integer
$num2 = 10.5; // float
$str = "10"; // string

var_dump(is_int($num1)); // bool(true)
var_dump(is_int($num2)); // bool(false)
var_dump(is_int($str));  // bool(false)
?>

In this example three variables are defined: $num1, $num2, and $str. Using var_dump() to display the result of is_int() shows true for the integer and false for the float and string.

Example 2

<?php
$var1 = 123;
$var2 = "abc";
$var3 = true;

if (is_int($var1)) {
    echo "Variable 1 is an integer";
} else {
    echo "Variable 1 is not an integer";
}

if (is_int($var2)) {
    echo "Variable 2 is an integer";
} else {
    echo "Variable 2 is not an integer";
}

if (is_int($var3)) {
    echo "Variable 3 is an integer";
} else {
    echo "Variable 3 is not an integer";
}
?>

This example defines three variables and uses if statements with is_int() to output messages indicating whether each variable is an integer.

In summary, is_int() is a handy PHP function for quickly checking if a variable is an integer, which is essential when handling different data types in development.