I have this piece of code:
var letters = ['A', 'B', 'C']
const letter1 = 'B'
for(var i=0; i<letters.length; i++) {
var letter = letters[i]
if (letter1 === letter) {
console.log(letter)
break
} else {
letters.push(letter1)
break
}
}
console.log(letters)
After running this code, I got this result:
['A', 'B', 'C', 'B']
But I want this result:
['A', 'B', 'C']
How can I do that?
The simplest solution is to check if the value is in the array before pushing it:
if (!letters.includes(letter1)) letters.push(letter1)
If you want to remove duplicates from an array, you can convert it to a Set and back again:
[...new Set(letters)]
Alternatively, you could just use a Set instead of an array, which is meant for storing unique values:
const letters = new Set(['A', 'B', 'C'])
// Use add instead of push (there is no push method on Set)
letters.add(letter1)
I'm not sure why you're pushing letter1 ('B') to the array if you don't want duplicates though.
function removeDuplicate(payload) {
const result = [];
payload.forEach(function(value) {
if(result.indexOf(value) == -1) {
result.push(value)
}
})
return value
}
Check if array has the element before inserting.
Array.proptotype.includes() will help
if(!extingArray.includes(element)) {
existingArray.push(element)
}
Use letters.pop() to remove any duplicates that might get entered into the end of the array.
