How to check list is present in other array list in java script ,with out loops

Question

checking obj2 is already exist in obj1

expected result is true but getting false

 var obj1 =[
    {Crane:1,Ladle:1},
    {Crane:1,Ladle:2},
    {Crane:2,Ladle:1},
    {Crane:2,Ladle:2}
    ];
    var obj2={Crane:2,Ladle:2}
                        // checking obj 2 is present in obj1
    if(obj1.includes(obj2))
    {
    console.log(true);
    }
    else
    {
    console.log(false);
    }

Does this answer your question? [Deep Compare JavaScript function](https://stackoverflow.com/questions/48728515/deep-compare-javascript-function) — Rainb, Dec 28 '19 at 11:47
What is the best way to check array is already exist in list — shashi sampige, Dec 28 '19 at 12:02

score 2 · Answer 1 · answered Dec 28 '19 at 12:23

Please find updated code for above problem::

var obj1 = [
    { name:"string1", value:"this" },
    { name:"string2", value:"this4"},
  { name:"string5", value:"this3"},
  { name:"string12", value:"this98"}
];
 var obj2={name:"string2",value:"this4"}
var foundValue = obj1.filter(obj=>obj.name===obj2.name);

console.log(foundValue);

 if(foundValue.length>0)
    {
    console.log(true);
    }
    else
    {
    console.log(false);
    }

score 1 · Answer 2 · answered Dec 28 '19 at 11:59

You can do something like this,

var obj1 = [
  { Crane: 1, Ladle: 1 },
  { Crane: 1, Ladle: 2 },
  { Crane: 2, Ladle: 1 },
  { Crane: 2, Ladle: 2 }
];

var obj2 = {Crane:2,Ladle:2}

const isPresent = (arr, obj2) => arr.some(obj => obj.Crane === obj2.Crane && obj.Ladle === obj2.Ladle);

if (isPresent(obj1, obj2)) {
    console.log(true);
} else {
    console.log(false);
}

score 0 · Answer 3 · answered Dec 28 '19 at 12:22

There is no simple answer to your question. For example, take a look at How to determine equality for two JavaScript objects? But in such a simple case as yours (if you have no cycle references, no special objects like Map, etc.) your can simply use stringify()

const obj1_str = JSON.stringify(obj1)
const obj2_str = JSON.stringify(obj2)
console.log(obj1_str.includes(obj2_str))

How to check list is present in other array list in java script ,with out loops

3 Answers3