Vowel/Consonant Check in JavaScript

1// Method 1: Using if-else
2function checkVowelConsonant(char) {
3    // Convert to lowercase for case-insensitive check
4    char = char.toLowerCase();
5    
6    if (char === 'a' || char === 'e' || char === 'i' || char === 'o' || char === 'u') {
7        return "Vowel";
8    } else if (char >= 'a' && char <= 'z') {
9        return "Consonant";
10    } else {
11        return "Not a letter";
12    }
13}
14
15console.log("a:", checkVowelConsonant('a'));
16console.log("B:", checkVowelConsonant('B'));
17console.log("z:", checkVowelConsonant('z'));
18console.log("5:", checkVowelConsonant('5'));
19
20// Method 2: Using array includes()
21function checkVowelConsonant2(char) {
22    char = char.toLowerCase();
23    const vowels = ['a', 'e', 'i', 'o', 'u'];
24    
25    if (vowels.includes(char)) {
26        return "Vowel";
27    } else if (char >= 'a' && char <= 'z') {
28        return "Consonant";
29    } else {
30        return "Not a letter";
31    }
32}
33
34console.log("\nUsing includes():");
35console.log("e:", checkVowelConsonant2('e'));
36console.log("k:", checkVowelConsonant2('k'));
37
38// Method 3: Using switch statement
39function checkVowelConsonant3(char) {
40    char = char.toLowerCase();
41    
42    switch(char) {
43        case 'a':
44        case 'e':
45        case 'i':
46        case 'o':
47        case 'u':
48            return "Vowel";
49        default:
50            if (char >= 'a' && char <= 'z') {
51                return "Consonant";
52            } else {
53                return "Not a letter";
54            }
55    }
56}
57
58console.log("\nUsing switch:");
59console.log("i:", checkVowelConsonant3('i'));
60console.log("m:", checkVowelConsonant3('m'));