Example 1: javascript remove duplicate in arrays
function removeDuplicates(array) {
return array.filter((a, b) => array.indexOf(a) === b)
};
function removeDuplicates(array) {
let x = {};
array.forEach(function(i) {
if(!x[i]) {
x[i] = true
}
})
return Object.keys(x)
};
function removeDuplicates(array) {
array.splice(0, array.length, ...(new Set(array)))
};
function removeDuplicates(array) {
let a = []
array.map(x =>
if(!a.includes(x) {
a.push(x)
})
return a
};
/THIS SITE/ "https://dev.to/mshin1995/back-to-basics-removing-duplicates-from-an-array-55he#comments"
Example 2: count duplicates array js
uniqueCount = ["a","b","c","d","d","e","a","b","c","f","g","h","h","h","e","a"];
var count = {};
uniqueCount.forEach(function(i) { count[i] = (count[i]||0) + 1;});
console.log(count);
Example 3: how to get duplicate values from array in javascript
var array = [1, 2, 2, 3, 3, 4, 5, 6, 2, 3, 7, 8, 5, 22, 1, 2, 511, 12, 50, 22];
console.log([...new Set(
array.filter((value, index, self) => self.indexOf(value) !== index))]
);
Example 4: javascript duplicate an array
let arr =["a","b","c"];
const duplicate = [...arr];
const duplicate = Array.from(arr);
Example 5: find duplicate values in array javascript
const findDuplicates = (arr) => {
let sorted_arr = arr.slice().sort();
let results = [];
for (let i = 0; i < sorted_arr.length - 1; i++) {
if (sorted_arr[i + 1] == sorted_arr[i]) {
results.push(sorted_arr[i]);
}
}
return results;
}
let duplicatedArray = [9, 4, 111, 2, 3, 4, 9, 5, 7];
console.log(`The duplicates in ${duplicatedArray} are ${findDuplicates(duplicatedArray)}`);
Example 6: javascript get duplicates in array
function getDuplicateArrayElements(arr){
var sorted_arr = arr.slice().sort();
var results = [];
for (var i = 0; i < sorted_arr.length - 1; i++) {
if (sorted_arr[i + 1] === sorted_arr[i]) {
results.push(sorted_arr[i]);
}
}
return results;
}
var colors = ["red","orange","blue","green","red","blue"];
var duplicateColors= getDuplicateArrayElements(colors);