How to split string when the value changes in JavaScript?

For this, you can use match() along with regular expression. Following is the code −

Example

var originalString="JJJJOHHHHNNNSSSMMMIIITTTTHHH";
var regularExpression=/(.)\1*/g;
console.log("The original string="+originalString);
var splitting=originalString.match(regularExpression);
console.log("After splitting the original string=");
console.log(splitting);

To run the above program, you need to use the following command −

node fileName.js.

Here, my file name is demo139.js.

Output

This will produce the following output −

PS C:\Users\Amit\JavaScript-code> node demo139.js
The original string=JJJJOHHHHNNNSSSMMMIIITTTTHHH
After splitting the original string=[
   'JJJJ', 'O',
   'HHHH', 'NNN',
   'SSS', 'MMM',
   'III', 'TTTT',
   'HHH'
]