PHPer脳の人がJavaScriptでループを回す

毎回for文書くたびに調べてるので

配列のforeach

phpだとこんな感じのやつ

$array = [1, 2, 3];

foreach($array as $a){
    echo $a;
}

// 1
// 2
// 3

jsだとこう

const array = [1, 2, 3];

for(let a of array){
    console.log(a);
}

// 1
// 2
// 3

連想配列のforeach

phpだとこんな感じのやつ

$array_assoc = [
    1 => 'one',
    2 => 'two',
    3 => 'three'
];

foreach($array_assoc as $k => $v){
    echo $k . ' is ' . $v . "\n";
}

// 1 is one
// 2 is two
// 3 is three

jsだとこう

const array_assoc = {
    1 : 'one',
    2 : 'two',
    3 : 'three'
};

for(let [k, v] of Object.entries(array_assoc)){
    console.log(k + ' is ' + v + "\n");
}

// 1 is one
// 2 is two
// 3 is three

※まあ、jsのObjectは正確には連想配列ではないけど