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JavaScript: Repeat a string a specified times

JavaScript String: Exercise-21 with Solution

Write a JavaScript function to repeat a string a specified times.

Test Data:
console.log(repeat_string('a', 4));
console.log(repeat_string('a'));
Output:
"aaaa"
"Error in string or count."

Pictorial Presentation:

JavaScript: Repeat a string a specified times

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Write a JavaScript function to repeat a string a specified times.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function repeat_string(string, count) 
  {
    if ((string == null) || (count < 0) || (count === Infinity) || (count == null))
      {
        return('Error in string or count.');
      }
        count = count | 0; // Floor count.
    return new Array(count + 1).join(string);
  }

console.log(repeat_string('a', 4));
console.log(repeat_string('a'));
console.log(repeat_string('a', -2));
console.log(repeat_string('a', Infinity));

Sample Output:

aaaa
Error in string or count.
Error in string or count.
Error in string or count.

Flowchart:

Flowchart: JavaScript: Repeat a string a specified times

Live Demo:

See the Pen JavaScript - common-editor-exercises by w3resource (@w3resource) on CodePen.


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Previous:Write a JavaScript function that can pad (left, right) a string to get to a determined length.
Next:Write a JavaScript function to get a part of string after a specified character.

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JavaScript: Tips of the Day

JavaScript: Implicit type coercion

function sum(a, b) {
  return a + b;
}

sum(1, '2');

JavaScript is a dynamically typed language: we don't specify what types certain variables are. Values can automatically be converted into another type without you knowing, which is called implicit type coercion. Coercion is converting from one type into another.

In this example, JavaScript converts the number 1 into a string, in order for the function to make sense and return a value. During the addition of a numeric type (1) and a string type ('2'), the number is treated as a string. We can concatenate strings like "Hello" + "World", so what's happening here is "1" + "2" which returns "12".

Ref: https://bit.ly/323Y0P6