JavaScript String Methods

🔹 What are String Methods?

JavaScript provides built-in methods to manipulate and work with strings. These methods allow you to modify, search, split, and format text efficiently.

🔹 Changing Case

1️⃣ `toUpperCase()` – Converts to Uppercase

let text = "hello world";
console.log(text.toUpperCase()); // "HELLO WORLD"

2️⃣ `toLowerCase()` – Converts to Lowercase

let text = "HELLO WORLD";
console.log(text.toLowerCase()); // "hello world"

🔹 Extracting Parts of a String

3️⃣ `slice(start, end)` – Extracts a Portion

let str = "JavaScript";
console.log(str.slice(0, 4)); // "Java"
console.log(str.slice(-6)); // "Script"

💡 Negative values start from the end.

4️⃣ `substring(start, end)` – Similar to `slice()` but No Negative Values

let str = "JavaScript";
console.log(str.substring(0, 4)); // "Java"

🔹 Searching in Strings

5️⃣ `indexOf(value)` – Finds First Occurrence

let sentence = "Learn JavaScript at JavaScript Academy!";
console.log(sentence.indexOf("JavaScript")); // 6

6️⃣ `lastIndexOf(value)` – Finds Last Occurrence

console.log(sentence.lastIndexOf("JavaScript")); // 21

7️⃣ `includes(value)` – Checks if a String Contains a Value

console.log(sentence.includes("Academy")); // true
console.log(sentence.includes("Python")); // false

🔹 Replacing Content

8️⃣ `replace(oldValue, newValue)` – Replaces First Occurrence

let phrase = "I love JavaScript!";
console.log(phrase.replace("JavaScript", "Coding")); // "I love Coding!"

9️⃣ `replaceAll(oldValue, newValue)` – Replaces All Occurrences

let text = "apple apple orange";
console.log(text.replaceAll("apple", "banana")); // "banana banana orange"

🔹 Trimming Extra Spaces

1️⃣ `trim()` – Removes Spaces from Start and End

let messyText = "   Hello World!   ";
console.log(messyText.trim()); // "Hello World!"

2️⃣ `trimStart()` – Removes Spaces from the Start

console.log(messyText.trimStart()); // "Hello World!   "

3️⃣ `trimEnd()` – Removes Spaces from the End

console.log(messyText.trimEnd()); // "   Hello World!"

🔹 Extracting Part of a String as an Array

1️⃣ `substr(start, length)` – Extracts Part of a String

let text = "JavaScript";
console.log(text.substr(4, 6)); // "Script"

💡 Deprecated but still works in older browsers.

🔹 Conclusion

JavaScript provides a variety of string methods to manipulate and format text efficiently. These methods help in modifying, searching, extracting, and trimming strings, making text handling much easier.

JAVASCRIPT

JavaScript String Methods

🔹 What are String Methods?

🔹 Changing Case

1️⃣ toUpperCase() – Converts to Uppercase

2️⃣ toLowerCase() – Converts to Lowercase

🔹 Extracting Parts of a String

3️⃣ slice(start, end) – Extracts a Portion

4️⃣ substring(start, end) – Similar to slice() but No Negative Values

🔹 Searching in Strings

5️⃣ indexOf(value) – Finds First Occurrence

6️⃣ lastIndexOf(value) – Finds Last Occurrence

7️⃣ includes(value) – Checks if a String Contains a Value