current community

your communities

more stack exchange communities

company blog
Stack Exchange Inbox Reputation and Badges
tour help
Join the Stack Overflow Community
Stack Overflow is a community of 6.5 million programmers, just like you, helping each other.
Join them; it only takes a minute:
Sign up
up vote 0 down vote favorite

I'm working on an Ionic hybrid app, but I'm quite new in Javascript / AngularJS.

I have this data structure:

  var objects= [
    {
      name: "o1",
      company: {
        id:2,
        fields: [1,6]
      }
    },
    {
      name: "o2",
      company: {
        id:2,
        fields: [3,4,5]
      }
    }
  ];

  var selectedFields= [
    {
      id: 1,
      name: "f1",
    },
    {
      id: 2,
      name: "f2",
    }
  ];

I want to filter the objects array elements which contains the ids (in the attribute company.fields) corresponding with the elements contained in selectedFields array.

For example, in this case, we have 2 elements, o1 and o2. o1 contains the fields 1 and 6, and o2 contains the fields 3, 4 and 5. The selectedFields array contains the fields with ids 1 and 2, so in this case the filtered object should be the object o1.

That's what I have tried:

var filteredObjects = filterFilter(objects, selectedFields,function(o, sf){
      return angular.forEach(o.company.fields, function (field) {
        return field.id == sf.is;
      });
});

But it says that o is undefined.

and: 

var result = [];
  angular.forEach(objects, function(o){
    angular.forEach(o.company.fields, function(f){
      angular.forEach(selectedFields, function(sf){
        if(sf.id == f.id) {
          result.push(o);
        }
      });
    });
  });

But the condition if(sf.id == f.id) is never true.

Any ideas? Thanks

share|improve this question
up vote 1 down vote accepted

Try this:

var test = objects.filter(function (o) {
    return selectedFields.some(function (i) {
        /*
            Some will return true if any of the elements return true
        */
        return i.id === o.company.id; 
    });
});

Essentially were filtering the Object array. .Filter() will create a new array with elements from the old one if its callback returns true. What .some() will do is return true if any any of its callbacks return true.

So .some() returns true if the id's match, which is passed into .filter() telling filter to add that element to the new array.

.some() is efficient in that it will stop iterating if it finds a matching result, callback that returns true. Whilst .forEach() will keep going and won't return a value.

http://jsfiddle.net/08tvmdyh/

Some Docs: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Array/some

List of very usefully Array methods: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array#Methods_2

EDIT: I misread your question sorry. 

var test = objects.filter(function (o) {
    return selectedFields.some(function (i) {
        /*
            Some will return true if any of the elements return true
        */
        return o.company.fields.indexOf(i.id) !== -1; //i.id === o.company.id; 
    });
});

Ive modified the fiddle: http://jsfiddle.net/08tvmdyh/1/

share|improve this answer
up vote 1 down vote

try this : 

    var filteredObjects = objects.filter(function(o){

        var fields = o.company.fields,
            matched = false;

        selectedFields.forEach(function(field){
          if(fields.indexOf(field.id) != -1){
            matched = true;
          }
        });

        return matched;
     });

First try to understand the following 3 native Array Functions built in Javascript : 

    Array.prototype.filter;
    Array.prototype.forEach;
    Array.prototype.indexOf;
share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.