TypeScript for..in Loop Example

This post shows how to use for..in loopTypeScript with an example.
Read more at https://www.javaguides.net/2019/10/typescript-for-loop-forof-loop-for-in.html

for..in loop Examples

The for...in loop iterates through a list or collection and returns an index on each iteration.
// for...in Loop example
let intArray = [10, 20, 30, 40];

for (var index in intArray) {
  console.log(index); // prints indexes: 0, 1, 2, 3

  console.log(intArray[index]); // prints elements: 10, 20, 30, 40
}

// iterate over object properties example
let user = {
    "firstName" : "ramesh",
    "lastName" : "fadatare",
    "fullName" : "ramesh fadatare"
}

for (const key in user) {
    if (user.hasOwnProperty(key)) {
        const element = user[key];
        console.log(element);
    }
}
Output:
C:\typescript-tutorial> tsc for-loops.ts
C:\typescript-tutorial> node for-loops.js
0
10
1
20
2
30
3
40
ramesh
fadatare
ramesh fadatare

Reference




Comments