how to count all occurences each letter in a string javascript code example

Example 1: count occurrences of character in string javascript

var temp = "This is a string.";
var count = (temp.match(/is/g) || []).length;
console.log(count);

Output: 2

Explaination : The g in the regular expression (short for global) says to search the whole string rather than just find the first occurrence. This matches 'is' twice.

Example 2: javascript count occurrences in string

function countOccurences(string, word) {
   return string.split(word).length - 1;
}
var text="We went down to the stall, then down to the river."; 
var count=countOccurences(text,"down"); // 2