How to use filter() to filter data in Javascript

How to filter variables for data types such as arrays and objects? This article mainly usesfilter()to filter a large amount of data to obtain the required data.

1.filter() syntax:

var newArray = arr.filter(callback(element[, index[, array]])[,thisArg])

callback() is a function used to test each element of the array and returns The value that results in true:

• element: The current element in the array.

• index: The index of the current element in the array.

• array: The array itself on which filter was called.

Return value: a filtered array

2. Example:

a. Filter the odd numbers in the array

arr5=[1,2,3,4,5]; res=arr5.filter( (item)=>item %2); console.log(res);

b. Filter the even numbers in the array

arr6=[1,2,3,4,5]; res=arr6.filter( (item)=>!(item %2)); console.log(res);

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