JavaScript: Insert a string within a specific position in another string

Last update on May 30 2022 10:00:19 (UTC/GMT +8 hours)

JavaScript String: Exercise-14 with Solution

Write a JavaScript function to insert a string within a string at a particular position (default is 1).

Test Data:
console.log(insert('We are doing some exercises.'));
console.log(insert('We are doing some exercises.','JavaScript '));
console.log(insert('We are doing some exercises.','JavaScript ',18));
"We are doing some exercises."
"JavaScript We are doing some exercises."
"We are doing some JavaScript exercises."

Pictorial Presentation:

JavaScript: Insert a string within a specific position in another string

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Insert a string within a specific position in another string</title>
</head>
<body>
</body>
</html>

JavaScript Code:

insert = function insert(main_string, ins_string, pos) {
   if(typeof(pos) == "undefined") {
    pos = 0;
  }
   if(typeof(ins_string) == "undefined") {
    ins_string = '';
  }
   return main_string.slice(0, pos) + ins_string + main_string.slice(pos);
    }
console.log(insert('We are doing some exercises.'));
console.log(insert('We are doing some exercises.','JavaScript '));
console.log(insert('We are doing some exercises.','JavaScript ',18));

Sample Output:

We are doing some exercises.
JavaScript We are doing some exercises.
We are doing some JavaScript exercises.

Flowchart:

Live Demo:

See the Pen JavaScript Insert a string within a specific position in another string - string-ex-14 by w3resource (@w3resource) on CodePen.

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Next: Write a JavaScript function to humanized number (Formats a number to a human-readable string.) with the correct suffix such as 1st, 2nd, 3rd or 4th.

JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04