Extract key values from one Array object and filter from other objects with the extracted values with underscore javascript

Question

var myArray = [{
    "name": "John Doe",
    "age": 29
}, {
    "name": "Anna Smith",
    "age": 24
}];

var myAnotherArray = [{
    "name": "John Doe",
    "age": 29
}, {
    "name": "Anna Smith",
    "age": 24
}, {
    "name": "Peter Jones",
    "age": 39
}, {
    "name": "Gabby",
    "age": 24
}, {
    "name": "Julian",
    "age": 29
}, {
    "name": "George",
    "age": 39
}];

I want to extact all age values from first array and then filter extracted values of age from second array.

Answer 1

You can use pluck to get the array of all the age from myArray . And then you can use filter , to filter the another array based on the age.

Demo

 var myArray = [{ "name": "John Doe", "age": 29 }, { "name": "Anna Smith", "age": 24 }]; var myAnotherArray = [{ "name": "John Doe", "age": 29 }, { "name": "Anna Smith", "age": 24 }, { "name": "Peter Jones", "age": 39 }, { "name": "Gabby", "age": 24 }, { "name": "Julian", "age": 29 }, { "name": "George", "age": 39 }]; var ages = _.pluck(myArray, 'age'); var filtered = _.filter(myAnotherArray, function(i, l) { return _.contains(ages, i.age); }); console.log(filtered); document.write(JSON.stringify(filtered));

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