JavaScript: Capitalize each word in the string

JavaScript String: Exercise-41 with Solution

Capitalize Every Word

Write a JavaScript function to capitalize each word in the string.

Test Data:
console.log(capitalizeWords('js string exercises'));
"JS STRING EXERCISES"

Visual Presentation:

Sample Solution:

JavaScript Code:

// Define a function called capitalizeWords that takes a string str as input
function capitalizeWords(str) {
    // Use the replace method with a regular expression \w\S* to match each word in the string
    // For each matched word, execute a callback function
    return str.replace(/\w\S*/g, function(txt) {
        // Inside the callback function, convert the first character of the word to uppercase
        // and keep the rest of the word unchanged
        return txt.substr(0).toUpperCase();
    });
}
// Call the capitalizeWords function with the input string 'js string exercises' and print the result to the console
console.log(capitalizeWords('js string exercises'));

Output:

JS STRING EXERCISES

Explanation:

In the exercise above,

• function capitalizeWords(str) {: Defines the function "capitalizeWords()" with a parameter 'str', representing the input string.
• return str.replace(/\w\S*/g, function(txt) {: Uses the "replace()" method with a regular expression '\w\S*' to match each word in the string. For each matched word, it executes a callback function.
• return txt.substr(0).toUpperCase(); });: In the callback function, it converts the first character of each word to uppercase using the "toUpperCase()" method and keeps the rest of the word unchanged.
• console.log(capitalizeWords('js string exercises'));: Calls the "capitalizeWords()" function with the input string 'js string exercises' and prints the capitalized string to the console.

Flowchart:

Live Demo:

See the Pen JavaScript Capitalize each word in the string-string-ex-41 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that converts every word in a string to uppercase.
• Write a JavaScript function that splits a string into words, converts each word entirely to uppercase, and rejoins them.
• Write a JavaScript function that uses a loop to iterate through each word and applies toUpperCase().
• Write a JavaScript function that handles punctuation by preserving non-alphabetic characters in the output.

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