ES6 Data Structure Map
Posted By : Manisha Kirodiwal | 30-Jul-2018
Maps in ES6
Using
var a = new Map()
a.set('x', 9)
a.set('z', 10)
// {"x” => 9, "z" => 10}
Map Methods and Properties
Using size property you can get
var a = new Map()
a.set('x', 9)
a.set('z', 10)
a.size; // 2 a; // Map(2) {"x” => 9, "z" => 10}
var a = new Map()
a.set('x', 9)
a.set('z', 10)
a.delete(‘x’); // true
a.delete(‘z’); // false (key not present)
a.get(‘x’); // 1
a.has(‘x’); // true
a.has('d'); // false
var a = new Map()
a.set('x', 9)
a.set('z', 10)
a.forEach((r, t, y) => console.log(`key:${r} value:${t} map:${y}`))
// key:1 value:x map:[Map Object]
// key:2 value:z map:[Map Object]
for([objkey,objvalue] of a)
console.log(objkey + '=' + objvalue)
// x=9
// z=10
var a = new Map()
a.set('x', 9)
a.set('z', 10)
var iterator = a.keys()
iterator.next(); // Object {value: "x", done: false}
iterator.next(); // Object {value: "z", done: false}
iterator.next(); // Object {value: undefined, done: true}
var iterator = a.values()
iterator.next(); // Object {value: 9, done: false}
iterator.next(); // Object {value: 10, done: false}
iterator.next(); // Object {value: undefined, done: true}
var iterator = a.entries()
iterator.next(); // Object {value: [""x, 9], done: false}
iterator.next(); // Object {value: ["z", 10], done: false}
iterator.next(); // Object {value: undefined, done: true}
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About Author
Manisha Kirodiwal
Manisha is a Web Application developer and she is good in working with Angular, TypeScript , JavaScript and Jquery. In free time she loves to dance and cooking.