为什么gettype（）表示它是double，但var_dump（）表示float？

Question

为什么gettype（）表示它是double，但var_dump（）表示float？

$number = 123456789; 
echo "Number: {$number} is a ". gettype($number) . "\n"; 
var_dump($number); 

响应：

编号：1.23456789012E + 18是双
浮动（1.23456789012E + 18）

Answer 1

他们是同样的事情http://php.net/manual/en/language.types.float.php

Answer 2

直接从PHP.net（gettype()）：

个为返回的字符串

候选条件值是：

... “双规”（由于历史原因，“双”返回在浮动的情况下，而不是简单的“浮动”） .. 。

Answer 3

<br> 
<?php 
     /*begins with a function that runs a Console msg for PHP */ 
function console_sn($txt){ 
$temp = ""; 
$temp .= "<script>"; 
$temp .= "console.info('frm_PHP: '+'"; 
$temp .= $txt; 
$temp .= "');"; 
$temp .= "</script>"; 
echo $temp; 
} 
echo("<br><hr><br>"); 
//end of PHP console function 

//Main primary code for this Example begins below 

//run these examples below in your test PHP file and see the results in your JS console window 

//e.g.#1 
$code1 = "1212"; 
console_sn(gettype(floatval($code1))); 

//e.g.#2 
$code2 = "1212sn"; 
console_sn(gettype(floatval($code2))); 

//e.g.#3 
$code3 = "1212"; 
console_sn(gettype((trim($code3))*1)); 

//e.g.#4 
$code4 = "1212sn"; 
console_sn(gettype((trim($code4))*1)); 

?>