Encrypting censored words using JavaScript

This tutorial demonstrates how to encrypt or mask censored words in JavaScript by applying specific transformation rules to convert regular text into a masked format.

Problem

We need to write a JavaScript function that takes in a string and converts it according to the following rules:

• All words should be in uppercase
• Every word should end with '!!!!'
• Any letter 'a' or 'A' should become '@'
• Any other vowel (E, I, O, U) should become '*'

Solution

Here's the implementation of the word masking function:

const str = 'ban censored words';
const maskWords = (str = '') => {
    let arr = str.split(' ');
    const res = [];
    
    for (let i = 0; i < arr.length; ++i) {
        let s = (arr[i].toUpperCase() + '!!!!').split('');
        
        for (let j = 0; j < s.length; ++j) {
            if (s[j] == 'A')
                s[j] = '@';
            if (s[j] == 'E' || s[j] == 'I' || s[j] == 'O' || s[j] == 'U')
                s[j] = '*';
        }
        res.push(s.join(''));
    }
    return res.join(' ');
};

console.log(maskWords(str));

B@N!!!! C*NS*R*D!!!! W*RDS!!!!

How It Works

The function processes the input string through these steps:

1. Split the string: Divides the input into individual words using space as delimiter
2. Process each word: Converts to uppercase and appends '!!!!'
3. Character transformation: Iterates through each character and applies vowel masking rules
4. Reconstruct: Joins characters back into words and words back into the final string

Alternative Implementation

Here's a more concise version using array methods and regular expressions:

const maskWordsAdvanced = (str = '') => {
    return str.split(' ')
        .map(word => word.toUpperCase() + '!!!!')
        .map(word => word.replace(/A/g, '@').replace(/[EIOU]/g, '*'))
        .join(' ');
};

const testStr = 'hello world amazing';
console.log(maskWordsAdvanced(testStr));

H*LL*!!!! W*RLD!!!! @M@Z*NG!!!!

Key Points

• The function handles empty strings with a default parameter
• Character replacement is case-sensitive after converting to uppercase
• The '!!!!' suffix is added before vowel replacement to avoid masking exclamation marks
• The algorithm preserves word boundaries and spacing

Conclusion

This word masking technique provides a simple way to obfuscate text by replacing vowels with symbols. It's useful for censoring content while maintaining readability and can be customized with different replacement rules.