loop through object array in javascript code example

Example 1: javascript loop through object example

var person={
 	first_name:"johnny",
  	last_name: "johnson",
	phone:"703-3424-1111"
};
for (var property in person) {
  	console.log(property,":",person[property]);
}

Example 2: javascript object array iteration

let obj = {
  key1: "value1",
  key2: "value2",
  key3: "value3"
}

Object.keys(obj).forEach(key => {
  let value = obj[key];
  //use key and value here
});

Example 3: javascript loop through object properties

for (var prop in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, prop)) {
        // do stuff
    }
}

Example 4: looping through an object of objects with arrays

let storeItems = {   
    eggs: {
      price: 3.77, quantity: 30
    },   
                  
    milk: {
      price: 2.22, quantity: 23
    },   
                   
    butter: {
      price: 2.00, quantity: 22
    },       
                   
    carrots: {
      price: 3.00, quantity: 11
    },   
                   
    beef: {
      price: 6.18, quantity: 34
    },   
    chicken: {
      price: 5.44, quantity: 34
    }
  };
  
  for(let item in storeItems) {   
    console.log(`${storeItems[item].quantity} ${item}s each cost ${storeItems[item].price}`);
}
  
  
// //OUTPUT:“30 eggs each cost 3.77”
// “23 milks each cost 2.22”
// “22 butters each cost 2”
// “11 carrots each cost 3”
// “34 beefs each cost 6.18”
// “34 chickens each cost 5.44”

Example 5: how to loop through an array of objects+

var arr = [[1,2], [3,4], [5,6]];
 for (var i=0; i < arr.length; i++) {
  for (var j=0; j < arr[i].length; j++) {
    console.log(arr[i][j]);
  }
}