PHP - is_int() 函数

定义和用法

is_int() 函数检查变量的类型是否为整数。

语法

bool is_int ( mixed $value )

参数

返回值

如果 value 是一个 int，则此函数返回 true，否则返回 false。

依赖

PHP 4 及以上版本

示例

以下示例演示了不同类型变量的返回值：

<?php
   $a = 33;
   echo "a is "; var_dump(is_int($a)); echo "<br>";

   $b = "33";
   echo "b is "; var_dump(is_int($b)); echo "<br>";

   $c = 33.5;
   echo "c is "; var_dump(is_int($c)); echo "<br>";

   $d = "33.5";
   echo "d is "; var_dump(is_int($d)); echo "<br>";

   $e = true;
   echo "e is "; var_dump(is_int($e)); echo "<br>";

   $f = false;
   echo "f is "; var_dump(is_int($f)); echo "<br>";

   $g = null;
   echo "g is "; var_dump(is_int($g)); echo "<br>";
?>

输出

这将产生以下结果：

a is bool(true)
b is bool(false)
c is bool(false)
d is bool(false)
e is bool(false)
f is bool(false)
g is bool(false)