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

JavaScript String: Exercise-14 with Solution

Insert in String

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."

Visual Presentation:

Sample Solution:

JavaScript Code:

// Define a function named insert that takes three parameters:
// main_string (the main string where ins_string will be inserted)
// ins_string (the string to insert into main_string)
// pos (the position in main_string where ins_string will be inserted)
insert = function insert(main_string, ins_string, pos) {
   // If pos is not provided, default it to 0
   if(typeof(pos) == "undefined") {
    pos = 0;
  }
   // If ins_string is not provided, default it to an empty string
   if(typeof(ins_string) == "undefined") {
    ins_string = '';
  }
   // Insert ins_string into main_string at position pos
   return main_string.slice(0, pos) + ins_string + main_string.slice(pos);
}
// Test cases to demonstrate the functionality of the insert function
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));

Output:

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

Explanation:

In the exercise above,

• The "insert()" function takes three parameters: 'main_string', 'ins_string', and 'pos'.
• If the 'pos' parameter is not provided, it defaults to 0.
• If the 'ins_string' parameter is not provided, it defaults to an empty string.
• The function then inserts the 'ins_string' into the 'main_string' at the specified position 'pos'.
• The modified 'main_string' with the 'ins_string' inserted is returned.

The provided test cases demonstrate the usage of the "insert()" function with different scenarios:

• Inserting nothing into the string "We are doing some exercises." at the beginning (position 0).
• Inserting "JavaScript " into the string "We are doing some exercises." at the beginning (position 0).
• Inserting "JavaScript " into the string "We are doing some exercises." at position 18.

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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