JavaScript: Reverse words in a given string

JavaScript String: Exercise-60 with Solution

Reverse Words

Write a JavaScript function to reverse words in a given string.
Test Data:
("abc") -> "cba"
("JavaScript Exercises") -> "tpircSavaJ sesicrexE"
(1234) -> "It must be a string."

Sample Solution:

JavaScript Code:

// Define a function named 'test' with a single parameter 'text'
function test(text) {
   // Check if the input string is empty
   if (text.length === 0) 
    {
    // Return a message if the input string is empty
    return 'String should not be empty!'
     }
   // Check if the input parameter 'text' is not a string
   if (typeof text !== 'string')
     {
       // Return a message if the input is not a string
       return 'It must be a string.'
     }
   // Create an empty array to store words
   var words = [];
  // Split the input text into an array of words using whitespace as the delimiter
  words = text.match(/\S+/g);
  // Create an empty string to store the reversed words
  var reverse_word = "";
  // Iterate through each word in the 'words' array
  for (var i = 0; i < words.length; i++) {
     // Reverse each word, join the characters, and add it to the 'reverse_word' string
     reverse_word += words[i].split('').reverse().join('') + " ";
  }
  // Return the string with reversed words
  return reverse_word
}
// Test the 'test' function with different input strings and output the result
console.log(test("abc"))  // 'cba'
console.log(test("JavaScript Exercises"))  // 'tpircsexE scirpSavaJ'
console.log(test(1234))  // It must be a string.

Output:

cba 
tpircSavaJ sesicrexE 
It must be a string.

Explanation:

In the exercise above,

• The function "test()" is defined, taking a single parameter named 'text'.
• It first checks if the input string is empty. If it is, the function returns a message indicating that the string should not be empty.
• Next, it checks if the input parameter 'text' is not a string using the 'typeof' operator. If it's not a string, the function returns a message indicating it must be a string.
• If the input is a non-empty string, the function splits the text into an array of words using a regular expression that matches non-whitespace characters.
• It then iterates through each word in the array of words.
• For each word, it splits it into an array of characters. It reverses the array, joins the characters back into a string, and adds it to the 'reverse_word' string with a space.
• After reversing each word, the function returns the string with reversed words.

Flowchart:

Live Demo:

See the Pen javascript-string-exercise-60 by w3resource (@w3resource) on CodePen.

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