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The `set()` method maps each players with their specified country.
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**Initialize a map with an iterable object**
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We can pass an iterable object to the `Map()` constructor.
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_Syntax:_
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`let map = new Map([iterable]);`
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_Code:_
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```js
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let fabThree =newMap([
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[kohli, "India"],
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[smith, "Australia"],
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[root, "England"],
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]);
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```
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**Getting an element from a map by Key**
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We can use the `get()` method to get an element from a map with key.
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```js
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fabThree.get(smith); //OUTPUT: Australia
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```
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If we somehow pass a key that does not exist, the `get()` method will return `undefined.`
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```js
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fabThree.get(foo); //OUTPUT: undefined
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```
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**Checking the existence of an element by Key**
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We can use the `has()` method to check if the key exists in the map.
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```js
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fabThree.has(bar); //OUTPUT: false
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fabThree.has(root); //OUTPUT: true
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```
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**Get the numbers of elements in the map**
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We can get the numbers of elements we have in the map with `size` property. The `size` property returns the number of elements in the Map object.
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```js
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console.log(fabThree.size); //OUTPUT: 3
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```
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**Iterate over map keys**
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We can use the `keys()` method to obtain the keys of the `Map` object. The `keys()` method returns a new iterator object that contains the keys of the elements in the map (return value - array).
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```js
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let virat = { fullName:"Virat Kohli" },
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smith = { fullName:"Steve Smith" },
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root = { fullName:"Joe Root" };
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let fabThree =newMap([
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[virat, "India"],
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[smith, "Australia"],
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[root, "England"],
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]);
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for (constplayeroffabThree.keys()) {
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console.log(player.fullName);
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}
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```
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_OUTPUT:_
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```
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Virat Kohli
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Steve Smith
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Joe Root
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```
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**Iterate over Map values**
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We can also iterate over values like with keys using `values()` method.
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```js
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let virat = { fullName:"Virat Kohli" },
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smith = { fullName:"Steve Smith" },
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root = { fullName:"Joe Root" };
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let fabThree =newMap([
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[virat, "India"],
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[smith, "Australia"],
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[root, "England"],
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]);
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for (constplayeroffabThree.values()) {
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console.log(player);
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}
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```
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_OUTPUT:_
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```
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India
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Australia
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England
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```
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**Iterate over entire map elements**
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We van use the `entries()` method to iterate over map elements. The `entries()` method returns an iteratorobject that contains array of `[key, value]` of each element in that Map object.
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```js
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let virat = { fullName:"Virat Kohli" },
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smith = { fullName:"Steve Smith" },
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root = { fullName:"Joe Root" };
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let fabThree =newMap([
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[virat, "India"],
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[smith, "Australia"],
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[root, "England"],
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]);
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for (let [player, country] offabThree.entries()) {
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console.log(`${player.fullName}: ${country});
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}
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```
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_OUTPUT:_
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```
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Virat Kohli: India
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Steve Smith: Australia
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Joe Root: England
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```
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We can also use `forEach()` instead of`for...of` loop.
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```js
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fabThree.foreach((player, country) => {
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console.log(`${player.fullName}: ${country}`);
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});
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```
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**Delete an element by Key**
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We can use the `delete()` method to delete an entry in the map.
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```
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fabThree.delete(root);
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```
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**Delete all elements in the map**
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We can clear all the entries in the Map object with the `clear()` method.
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