Home Backend Development PHP Tutorial PHP数组传递是值传递而非引用传递概念纠正_PHP

PHP数组传递是值传递而非引用传递概念纠正_PHP

Jun 01, 2016 pm 12:08 PM
Pass by value pass by reference

在调用函数时通过将PHP数组作为实参赋给形参,在函数中修改,并不会影响到数组本身。

说明此过程中的传递为值传递,数组变量并非是指向此数组本身的引用,PHP数组本身以值的形式存在,同时形参是对数组的拷贝。

这点与其他一些语言不同(如c、Js等)很不相同,值得注意!
复制代码 代码如下:
$arr = array(
'name' => 'corn',
'age' => '24',
);
test_arr($arr);
function test_arr($arr){
$arr['name'] = 'qqyumidi';
}
print_r($arr); //result: Array ( [name] => corn [age] => 24 )

Js代码如下:
复制代码 代码如下:
var arr = new Array('corn', '24');
test_arr(arr);
function test_arr(arr){
arr[0] = 'qqyumidi';
}
console.log(arr); //result:["qqyumidi", "24"]

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