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javascriptarraysreact-nativefiltergrouping

How to filter array of objects in react native?


I want to filter this data array into state and city array. How can I achieve this using lodash or any other better way rather than for loop and maintaining extra arrays.

data: [
    { id: 1, name: Mike, city: philps, state: New York},
    { id: 2, name: Steve, city: Square, state: Chicago},
    { id: 3, name: Jhon, city: market, state: New York},
    { id: 4, name: philps, city: booket, state: Texas},
    { id: 5, name: smith, city: brookfield, state: Florida},
    { id: 6, name: Broom, city: old street, state: Florida},
]

which user click state, list of state appears.

{state: New York, count: 2},
{state: Texas, count: 1},
{state: Florida, count: 2},
{state: Chicago, count: 1},

When user click particular state, list of cities of that state appears. For ex. when user clicks New York state,

{id:1, name: Mike, city: philps}
{id:3, name: Jhon, city: market}

Solution

  • With lodash, you could use _.filter with an object as _.matches iteratee shorthand for filtering the object with a given key/value pair and

    use _.countBy with _.map for getting a count of states.

    var data = [{ id: 1, name: 'Mike', city: 'philps', state: 'New York' }, { id: 2, name: 'Steve', city: 'Square', state: 'Chicago' }, { id: 3, name: 'Jhon', city: 'market', state: 'New York' }, { id: 4, name: 'philps', city: 'booket', state: 'Texas' }, { id: 5, name: 'smith', city: 'brookfield', state: 'Florida' }, { id: 6, name: 'Broom', city: 'old street', state: 'Florida' }];
    
    console.log(_.filter(data, { state: 'New York' }));
    console.log(_
        .chain(data)
        .countBy('state')
        .map((count, state) => ({ state, count }))
        .value()
    );
    .as-console-wrapper { max-height: 100% !important; top: 0; }
    <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.15.0/lodash.min.js"></script>