I have this data and need to apply all the filters using lodash. The final output is blank.
filters = [{'gender':'M'}, {'division':'police'}]
data = [{'name':'tom', 'gender':'M', 'division':'police'},
{'name':'bob' , 'gender':'M', 'division':'police'},
{'name':'dave' , 'gender':'F', 'division':'IT'},
]
data = _.filter(data, function(item){
_.forEach(filters, function(filter){
data_found = _.filter([item], filter)
console.log('data_found - ', data_found)
})
})
console.log(data)
https://jsfiddle.net/52k6170c/1/
You can combine your filters array to a single object and use that as your filter
combined = filters.reduce((acc,item) => ({...acc, ...item}))
// combined is = {'gender':'M', 'division':'police'}
data = _.filter(data, combined)
if you feel like not using the rest operators, there is a lodash function that combines the array of objects into a single object
You can just combine both filter into one. Something like this
_.filter(data, function(item){
if(item.gender === 'M' && item.division === 'police') return item;
})
This would give you all records with gender-male and division-police
You can use the _.filter method along with the _.every method to filter a collection based on another collection of predicates (I'm using arrow functions here). This example also assumes your filter objects only have a single key/value pair as in your example:
const filteredData = _.filter(data, item => {
return _.every(filters, filter => {
let filterKey = Object.keys(filter)[0]
return item[filterKey] === filter[filterKey]
})
})
A cleaner solution would be to combine your filters into a single object, and use the _.matches method to do a comparison:
const filter = { gender: 'M', division: 'police' }
const filteredData = _.filter(data, _.matches(filter))
Related
We have an array of objects like
const arr = [{id: "someId", name: {...}}, ...];
const skippedKeys = ["id"...]
How can i filtered the array of object based on skipped keys?
The result should be:
const result = [{name: {...}}, ...];
Also i don't want to make a cycle inside the cycle.
the result also could be implemented using lodash library.
we should remove key with value as well.
Since you stated that it could be implemented using lodash, here is some code using lodash:
let result = _.map(arr, (el)=> _.omit(el, skippedKeys))
const result = arr.map(obj =>
Object.keys(obj).reduce(
(res, key) => (
skippedKeys.includes(key) ? res : {...res, [key]: obj[key]}
),
{},
));
It's simple and no need for any nested cycles. There are two option to do that
Using includes function
const result = arr.filter((item) => !result.includes(item.id));
Using set
const dataSet = new Set(skippedKeys);
const result = arr.filter((item) => !dataSet.has(item.id));
I prefer the second one as it excludes double checks. Hope the answer was helpful.
I want to push object that only have unique id1 into array.
Example:
let array = [],
obj = {},
access = true
if(access){
obj['id1'] = 1
obj['id2'] = 2
if(array.indexOf(obj.id1) == -1){
array.push(obj)
}
}
console.log(array);
In the above example I am trying to add value to obj then push the obj into array. But obj.id1 need to be unique. The method I am using above doesn't work in my case.
Thank you
As Taplar says, indexOf will look for the first instance of the thing you pass in in the other array. This won't work because there are no instances of the ids in the array, directly anyway.
Use the find function, which allow you pass in a comparison function, so you can define what a match is.
let initial = [{id:1}, {id:2}, {id:1}];
let result = initial.reduce((acc, item) =>
{
if(!acc.find(other => item.id == other.id))
{
acc.push(item);
}
return acc;
}, []);
console.log(result);
Simplest solution . Lets say myObjArray have duplicate object use below es6 code to get unique array from that
// Creates an array of objects with unique "name" property values.
let uniqueObjArray = [
...new Map(myObjArray.map((item) => [item["name"], item])).values(), ]; console.log("uniqueObjArray", uniqueObjArray);
Refer here for more detail https://yagisanatode.com/2021/07/03/get-a-unique-list-of-objects-in-an-array-of-object-in-javascript/
I think you need to use findIndex and not indexOf.
Try replacing your if condition with the following:
array.findIndex((o)=>{ return o.id1 === obj.id1 }) === -1
In my JS project, I am using Lodash library to Extract property, split array, get unique values.
var taskobj = [
{'taskno':'a', 'team':'1,2'},
{'taskno':'b', 'team':'3,4'},
{'taskno':'c', 'team':'2,4'},
];
//Looping through the object to convert string to array
_.forEach(taskobj, function(value, key) {
taskobj[key].team = _.split(taskobj[key].team,',');
});
// using _.map to extract team and return array
// using _.flatten to flatten array
// using _.uniq to get unique values from flattned array.
return _.uniq(_.flatten(_.map(taskobj,'team')));
// logs - [1,2,3,4]
Is this the most efficient way to achieve this?
you can use reduce and start with a new Set() and add the values of team every time ( then convert it back to an array with the spread operator )
var taskobj = [
{'taskno':'a', 'team':'1,2'},
{'taskno':'b', 'team':'3,4'},
{'taskno':'c', 'team':'2,4'},
];
var result = [...taskobj.reduce((acc, {team}) => {
team.split(',').forEach(e => acc.add(e))
return acc
}, new Set())]
console.log(result)
This can be achieved by using lodash#flatMap with an iteratee that splits the team string into an array, which is then flattened by the mentioned function and then use lodash#uniq to get the final result.
var result = _.uniq(_.flatMap(taskobj, ({ team }) => team.split(',')));
var taskobj = [
{'taskno':'a', 'team':'1,2'},
{'taskno':'b', 'team':'3,4'},
{'taskno':'c', 'team':'2,4'},
];
var result = _.uniq(_.flatMap(taskobj, ({ team }) => team.split(',')));
console.log(result);
.as-console-wrapper{min-height:100%;top:0}
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.min.js"></script>
Use simpler version
try this
var teams = [];
var taskobj = [
{'taskno':'a', 'team':'1,2'},
{'taskno':'b', 'team':'3,4'},
{'taskno':'c', 'team':'2,4'},
];
taskobj.map(obj => {
var teamSplit = obj.team.split(',');
teams = [...teams, ...teamSplit];
})
var uniqTeams = _.uniq(teams);
console.log('teams', teams);
console.log('uniqTeams', uniqTeams)
JsBin link
http://jsbin.com/bedawatira/edit?js,console
I am looking for a short and efficient way to filter objects by key, I have this kind of data-structure:
{"Key1":[obj1,obj2,obj3], "Key2":[obj4,obj5,obj6]}
Now I want to filter by keys, for example by "Key1":
{"Key1":[obj1,obj2,obj3]}
var object = {"Key1":[1,2,3], "Key2":[4,5,6]};
var key1 = object["Key1"];
console.log(key1);
you can use the .filter js function for filter values inside an object
var keys = {"Key1":[obj1,obj2,obj3], "Key2":[obj4,obj5,obj6]};
var objectToFind;
var keyToSearch = keys.filter(function(objects) {
return objects === objectToFind
});
The keyToSearch is an array with all the objects filter by the objectToFind variable.
Remember, in the line return objects === objectToFind is where you have to should your statement. I hope it can help you.
You can create a new object based on some custom filter criteria by using a combination of Object.keys and the array .reduce method. Note this only works in es6:
var myObject = {"Key1":["a","b","c"], "Key2":["e","f","g"]}
function filterObjectByKey(obj, filterFunc) {
return Object.keys(obj).reduce((newObj, key) => {
if (filterFunc(key)) {
newObj[key] = obj[key];
}
return newObj;
}, {});
}
const filteredObj = filterObjectByKey(myObject, x => x === "Key1")
console.log(filteredObj)
Not sure what exactly are you trying to achieve, but if you want to have a set of keys that you would like to get the data for, you have quite a few options, one is:
var keys = ['alpha', 'bravo'];
var objectToFilterOn = {
alpha: 'a',
bravo: 'b',
charlie: 'c'
};
keys.forEach(function(key) {
console.log(objectToFilterOn[key]);
});
So I'm getting this from backend:
{"Item":{"userEmail":"b","Username":"bUsername","Push":"sdsdsd","Password":"sdsds","Buddy":{"datatype":"SS","contents":{"Drake":"Drake","Ola":"Ola","b":"b","d":"d"}}}}
I use Object.Keys to narrow down the contents to:
Drake,Ola,b,d
Which I then map to give:
[{"id":"Drake"},{"id":"Ola"},{"id":"b"},{"id":"d"}]
Which is then used on my Angular Front-end as .id. I want to remove the last letter from each value i.e leaving Drak,Ol etc. I've tried many ways but have failed, how can I achieve this please so that the id has those values?
EDIT
I also want to now get that value that was cut AND add it such that the end product will be [{"id":"Drak",valueThatWasCut:"e"}]
You could iterate the object's keys and build with the short string a new object.
var data = {"Item":{"userEmail":"b","Username":"bUsername","Push":"sdsdsd","Password":"sdsds","Buddy":{"datatype":"SS","contents":{"Drake":"Drake","Ola":"Ola","b":"b","d":"d"}}}},
ids = Object.keys(data.Item.Buddy.contents).reduce(function (r, k) {
var n = k.slice(0, -1);
return n ? r.concat({ id: n }) : r;
}, []);
console.log(ids);
Perhaps something like :
var arr = [{"id":"Drake"},{"id":"Ola"},{"id":"b"},{"id":"d"}];
var result = arr.map(x => x.id.slice(0,-1));
console.log(result); // [ 'Drak', 'Ol', '', '' ]
Create a temporary contents object and change in that.
Then just set this in the original object. ES6 spread operators would save the rest of data without respecifying all keys and values.
let items = {"Item:{"userEmail":"b","Username":"bUsername","Push":"sdsdsd","Password":"sdsds","Buddy":{"datatype":"SS","contents":{"Drake":"Drake","Ola":"Ola","b":"b","d":"d"}}}};
let contents = items.Item.Buddy.contents;
let contentsNew = Object.keys(contents).map((content) => {
return {[content.substring(0, content.length-1)]: content.substring(0, content.length-1), valueThatWasCut: content[content.length-1]};
});
items = {...items, Item: {...items.Item,Buddy:{...items.Item.Buddy,contents: contentsNew}}};
console.log(items);