CODEWITHSUNDEEP
javascriptarraysobjectiterationunderscore.js
Patrick
Patrick

Reputation: 4298

Check if there are null values in an array of objects

I have this array of objects.

[Object, Object, Object]
0:Object
 name: "Rick"
 Contact: "Yes"
 Date:'null'
 Location:'null'
1:Object
 name:"Anjie"
 Contact:"No"
 Date:'13/6/2016'
 Location:'LA'
2:Object
 name:"dillan"
 Contact:"Maybe"
 Date:'17/6/2016'
 Location:'NY'

As you can see, there are null values for Object[0] for Date and Location. I want to check if there is a null value present in the entire array of Objects. If there is a null value present for 'Date' and 'Location', i should be able to display 'Null present' at the console. If no null values are present, it should display 'Data right' at the console.

can someone please let me know how to achieve this.

Upvotes: 2

Views: 8745

Answers (4)

Gruff Bunny
Gruff Bunny

Reputation: 27976

A solution using underscore:

var nullPresent = _.some(data, item => _.some(_.pick(item, 'Date', 'Location'), _.isNull));

Upvotes: 2

epascarello
epascarello

Reputation: 207501

Use some() and check if there is a null.

var arr = [
   { a : "a", b : "b", c : "c" },
   { a : "a", b : "b", c : "c" },
   { a : "a", b : "b", c : null }
];

function hasNull(element, index, array) {
  return element.a===null || element.b===null || element.c===null;
}
console.log( arr.some(hasNull) );

If you do not want to hardCode the if, than you need to add another loop and loop over the keys.

var arr = [
   { a : "a1", b : "b1", c : "c1" },
   { a : "a2", b : "b2", c : "c2" },
   { a : "a3", b : "b3", c : null }
];

function hasNull(element, index, array) {
  return Object.keys(element).some( 
    function (key) { 
      return element[key]===null; 
    }
  ); 
}
console.log( arr.some(hasNull) );

or JSON with a reg exp (

var arr = [
   { a : "a1", b : "b1", c : "c1" },
   { a : "a2", b : "b2", c : "c2" },
   { a : "a3", b : "b3", c : null }
];

var hasMatch = JSON.stringify(arr).match(/:null[\},]/)!==null;
console.log(hasMatch);

Upvotes: 2

Pranav C Balan
Pranav C Balan

Reputation: 115202

Do it using Object.keys() and Array#some methods

var data = [{
  name: "Rick",
  Contact: "Yes",
  Date: null,
  Location: null
}, {
  name: "Anjie",
  Contact: "No",
  Date: '13/6/2016',
  Location: 'LA'
}, {
  name: "dillan",
  Contact: "Maybe",
  Date: '17/6/2016',
  Location: 'NY'
}];


// iterate over array elements
data.forEach(function(v, i) {
  if (
    // get all properties and check any of it's value is null
    Object.keys(v).some(function(k) {
      return v[k] == null;
    })
  )
    console.log('null value present', i);
  else
    console.log('data right', i);
});

Upvotes: 6

Eduard Void
Eduard Void

Reputation: 2714

var wasNull = false;
for(var i in objectsArray) {
  if(objectsArray[i].Date == null || objectsArray[i].Location == null) wasNull = true;
}
if(wasNull) console.log('Was null');
else console.log('Data right');

Upvotes: 5

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