JavaScript: Make capitalize the first letter of each word in a string
JavaScript String: Exercise-9 with Solution
Capitalize Each Word
Write a JavaScript function to capitalize the first letter of each word in a string.
Test Data:
console.log(capitalize_Words('js string exercises'));
"Js String Exercises"
Visual Presentation:

Sample Solution:
JavaScript Code:
// Define a function named capitalize_Words that takes a string str as input
function capitalize_Words(str)
{
// Use the replace method with a regular expression to match words (\w) followed by zero or more non-space characters (\S*)
// For each matched word, use a callback function to capitalize the first character and convert the rest of the characters to lowercase
return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});
}
// Call the capitalize_Words function with the argument 'js string exercises' and output the result
console.log(capitalize_Words('js string exercises'));
Output:
Js String Exercises
Explanation:
In the exercise above,
- The function "capitalize_Words()" is defined with a single parameter 'str', representing the input string.
- Within the function, a regular expression (/\w\S*/g) is used with the "replace()" method to match words in the string.
- For each matched word, a callback function is invoked, which capitalizes the first character using 'txt.charAt(0).toUpperCase()' and converts the rest of the characters to lowercase using 'txt.substr(1).toLowerCase()'.
- The "replace()" method replaces each matched word with the modified version (capitalized first letter and lowercase rest).
- Finally, the modified string is returned from the function.
Flowchart:

Live Demo:
See the Pen JavaScript Make capitalize the first letter of each word in a string - string-ex-9 by w3resource (@w3resource) on CodePen.
For more Practice: Solve these Related Problems:
- Write a JavaScript function that splits a string into words, capitalizes the first letter of each, and rejoins them.
- Write a JavaScript function that uses map() to process each word and convert its first character to uppercase.
- Write a JavaScript function that handles punctuation and ensures only alphabetical characters are capitalized.
- Write a JavaScript function that converts a sentence to title case using regular expressions and string replacement.
Go to:
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