06c08-2.php

来自「介绍PHP5的给类型函数应用」· PHP 代码 · 共 30 行

<?php
// Define an function that does lots of type checking
function many_hints($int, $flt, $str) {
    // Ensure that $int is an integer
    if (!(is_integer($int))) {
        trigger_error('$int is not of type integer', E_USER_ERROR);
    }
    // Ensure that $flt is an float
    if (!(is_float($flt))) {
        trigger_error('$flt is not of type float', E_USER_ERROR);
    }
    // Ensure that $str is an string
    if (!(is_string($str))) {
        trigger_error('$str is not of type integer', E_USER_ERROR);
    }
    
    // Now that we know we have proper variables, multiply the integer &
    //  float together and return that with the string
    return ($int * $flt) . ' ' . $str;
}

// Use this first giving it valid parameters
//  This will print: '83.664 dollars owed'
echo '<p>', many_hints(1992, .042, 'dollars owed'), '</p>';

// Now try it again, Passing it incorrect data types.
//  An error will be generated because of the type mismatch.
echo '<p>', many_hints('bob', 3, true), '</p>';
?>