What is array indexOf() in Javascript?
Overview
The indexOf function in Javascript is used to find the index of a particular key in the array. The general syntax for indexOf is:
array.indexOf(keyName);
Parameters
The function indexOf takes one single mandatory input as an argument. The mandatory input is the name of the key we want the index of.
Return value
The function indexOf returns the index of the key.
Example
The following example will help you understand the function indexOf more clearly. First, we create an array of names. Then, we use the function indexOf to find the index of the name “Sana.” Lastly, we print the index.
const names = ["Samia", "Sana", "Ali"];const ind = names.indexOf("Sana");console.log(ind);
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