let str = "Please locate where 'locate' occurs!";

str.indexOf("locate");

​

//it will returns the index of (the position of) the first occurrence of a specified text in a string:

// >> 7

​

//if you find this answer is useful ,

//upvote ⇑⇑ , so can the others benefit also . @mohammad alshraideh ( ͡~ ͜ʖ ͡°)

//indexOf getting index of array element, returns -1 if not found

var colors=["red","green","blue"];

var pos=colors.indexOf("blue");//2

​

//indexOf getting index of sub string, returns -1 if not found

var str = "We got a poop cleanup on isle 4.";

var strPos = str.indexOf("poop");//9

const paragraph = 'The quick brown fox';

​

console.log(paragraph.indexOf('T'));

>> 0

​

console.log(paragraph.indexOf('h'));

>> 1

​

console.log(paragraph.indexOf('Th'));

>> 0

​

console.log(paragraph.indexOf('he'));

>> 1

​

console.log(paragraph.indexOf('x'));

>> 18

// indexOf method only requires a single value 

// and returns the index of the FIRST value found in array

const cities = [

  "Orlando",

  "Dubai",

  "Denver",

  "Edinburgh",

  "Chennai",

  "Accra",

];

​

console.log(cities.indexOf("Chennai"));

// expected output is 4

str.indexOf(searchValue[, fromIndex])

var str = "We got a poop cleanup on isle 4.";

var strPos = str.indexOf("5");//9

var text = "Find the word location in this sentence";

text.indexOf("location");

​