foreach through object javascript code example

Example 1: foreach object javascript

const students = {
  adam: {age: 20},
  kevin: {age: 22},
};

Object.entries(students).forEach(student => {
  // key: student[0]
  // value: student[1]
  console.log(`Student: ${student[0]} is ${student[1].age} years old`);
});
/* Output:
Student: adam is 20 years old
Student: kevin is 22 years old
*/

Example 2: javascript foreach object

const list = {
  key: "value",
  name: "lauren",
  email: "[email protected]",
  age: 30
};

// Object.keys returns an array of the keys
// for the object passed in as an argument.

Object.keys(list).forEach(val => {
  let key = val;
  let value = list[val];
  console.log(`${key} : ${value}`);
});

// Returns:
// "key : value"
// "name : lauren";
// "email : [email protected]"
// "age : 30"

Example 3: foreach object javascript

const obj = {
  a: "aa",
  b: "bb",
  c: "cc",
};
//This for loop will loop through all keys in the object.
// You can get the value by calling the key on the object with "[]"
for(let key in obj) {
  console.log(key);
  console.log(obj[key]);
}

//This will return the following:
// a
// aa
// b
// bb
// c
// cc

Example 4: foreach object javascript

Add thisvar p = {
    "p1": "value1",
    "p2": "value2",
    "p3": "value3"
};

for (var key in p) {
    if (p.hasOwnProperty(key)) {
        console.log(key + " -> " + p[key]);
    }
}

Example 5: js object for each

const obj = {
  a: 1, 
  b: 2, 
  c: 3
};
    
for (let key in obj) {
  console.log(key + " = " + obj[key]);
}
// Ausgabe:
// "a = 1"
// "b = 2"
// "c = 3"

Example 6: javascript foreach object

function logArrayElements(element, index, array) {
  console.log('a[' + index + '] = ' + element)
}

// Notice that index 2 is skipped, since there is no item at
// that position in the array...
[2, 5, , 9].forEach(logArrayElements)
// logs:
// a[0] = 2
// a[1] = 5
// a[3] = 9