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JavaScript: Input a string and converts upper case letters to lower and vice versa

JavaScript String: Exercise-10 with Solution

Write a JavaScript function that takes a string which has lower and upper case letters as a parameter and converts upper case letters to lower case, and lower case letters to upper case.

Test Data:
console.log(swapcase('AaBbc'));
"aAbBC"

Pictorial Presentation:

JavaScript: Input a string and converts upper case letters to lower and vice versa

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JS swap case</title>
</head>
<body>
</body>
</html>

JavaScript Code:

swapcase = function swapcase(str) {
        return str.replace(/([a-z]+)|([A-Z]+)/g, function(match, chr) {
            return chr ? match.toUpperCase() : match.toLowerCase();
        });
    }
console.log(swapcase('AaBbc'));

Sample Output:

aAbBC

Flowchart:

Flowchart: JavaScript- Input a string and converts upper case letters to lower and vice versa

Live Demo:

See the Pen JavaScript Input a string and converts upper case letters to lower and vice versa - string-ex-10 by w3resource (@w3resource) on CodePen.


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Next: Write a JavaScript function to convert a string into camel case.

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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