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[Js] Map 본문

WEB/JavaScript

[Js] Map

애플쩀 2022. 6. 9. 08:08 
<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<title>2022.06.08 11:19:22</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>
</head>
<body>
<h3>ex02.html</h3>
//js Set
//js Map
//key- value ,한쌍 entry 
//1.new Map()
//2.set()/ get() /delete()/ for each /size
//3.entries() 

<script>
    var fruits=new Map();
    console.log(fruits.size); //0 
    fruits.set("apple",10);
    fruits.set("banana",20);
    fruits.set("orange",15);
    console.log(fruits.size);
    console.log(fruits.get("banana"));

    console.log(fruits.has("apple"));

    fruits.forEach(function(value, key, map){
        console.log(key+"/"+value);
    });
/*     apple/10
 banana/20
 orange/15
 */

 for(let entry of fruits.entries()){
     console.log(entry);
 
 }
/* (2) ['apple', 10]
(2) ['banana', 20]
(2) ['orange', 15] */


</script>

</body>
</html>

 

<!DOCTYPE html>
<html lang="ko">
<head>
<meta charset="UTF-8">
<title>2022.06.09 08:02:02</title>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>
</head>
<body>
<h3>map.html</h3>
<script>
    var fruits=new Map();
    console.log(fruits.size); //0 
    fruits.set("apple",10);
    fruits.set("banana",23);
    console.log(fruits.size); //2
    fruits.set("apple",10);
    fruits.set("banana",23);
    console.log(fruits.size); //2 중복x
    console.log(fruits.get("banana"));
    console.log(fruits.has("banana"));
    fruits.forEach(function(elt, i ,array){
        console.log(i+","+elt);
    });
for(let entry of fruits.entries()){
    console.log(entry);
}for(let entry of fruits){
    console.log(entry);
}

</script>
</body>
</html>
for(let entry of fruits.entries()){
    console.log(entry);
}
for(let entry of fruits){
    console.log(entry);
}

//두개 다 가능하다. .entries()안써도 가능
저작자표시 (새창열림)

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