What is the usage of for of in es6

In es6, "for of" is used to traverse the data structure deployed with the "Symbol.iterator" attribute. The "for of" loop is a method of traversing all data structures. The syntax is "for(var value of Data structure object){console.log(value);}".

The operating environment of this tutorial: Windows 10 system, ECMAScript version 6.0, Dell G3 computer.

What is the usage of for of in es6

ES6 introduces the for...of loop as a unified method to traverse all data structures.

As long as a data structure is deployed with the Symbol.iterator attribute, it is regarded as having an iterator interface, and its members can be traversed using a for...of loop, that is, for... What is called inside the of loop is the Symbol.iterator method of the data structure.

The range that the for...of loop can use:

• String;

• Array;

• Set and Map structures;

• Some array-like objects (such as arguments objects, DOM NodeList objects);

• Generator object.

Usage example

var arr = ['nick','freddy','mike','james'];
for(var item of arr){
    console.log(item);
}

Output result:

Traverse each item in the array.

Usage example

var arr = [
    { name:'nick', age:18 },
    { name:'freddy', age:24 },
    { name:'mike', age:26 },
    { name:'james', age:34 }
];
for(var item of arr){
    console.log(item.name,item.age);
}

Output result:

Traverse each item in the array.

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