README.md

JavaScript String Methods

This document provides a list of commonly used JavaScript string methods along with examples of how to use them.

List of Methods

1. charAt(index)
2. charCodeAt(index)
3. concat(...strings)
4. includes(searchString, position)
5. indexOf(searchValue, fromIndex)
6. lastIndexOf(searchValue, fromIndex)
7. match(regexp)
8. repeat(count)
9. replace(searchValue, newValue)
10. slice(beginIndex, endIndex)
11. split(separator, limit)
12. substring(indexStart, indexEnd)
13. toLowerCase()
14. toUpperCase()
15. trim()
16. startsWith(searchString, position)
17. endsWith(searchString, length)
18. padStart(targetLength, padString)
19. padEnd(targetLength, padString)
20. fromCharCode(...codes)
21. at(index)
22. codePointAt(index)
23. normalize(form)
24. trimStart() or trimLeft()
25. trimEnd() or trimRight()

Method Usages

• charAt(index)

const str = "Hello";
console.log(str.charAt(1)); // 'e'

• charCodeAt(index)

//Returns the Unicode of the character at the specified index.
const str = "Hello";
console.log(str.charCodeAt(1)); // 101

• concat(...strings)

//Combines two or more strings.
const str1 = "Hello";
const str2 = "World";
console.log(str1.concat(" ", str2)); // "Hello World"

• includes(searchString, position)

//Checks if a string contains a specified value.
const str = "Hello World";
console.log(str.includes("World")); // true

• indexOf(searchValue, fromIndex)

//Returns the index of the first occurrence of a specified value.
const str = "Hello World";
console.log(str.indexOf("World")); // 6

• lastIndexOf(searchValue, fromIndex)

//Returns the index of the last occurrence of a specified value.
const str = "Hello World Hello";
console.log(str.lastIndexOf("Hello")); // 12

• match(regexp)

//Executes a search for a match between a regular expression and the string.
const str = "The quick brown fox";
const result = str.match(/quick/);
console.log(result[0]); // "quick"

• repeat(count)

//Returns a new string with a specified number of copies of the original string.
const str = "Hello";
console.log(str.repeat(3)); // "HelloHelloHello"

• replace(searchValue, newValue)

//Replaces the first occurrence of a specified value with a new value.
const str = "Hello World";
console.log(str.replace("World", "JavaScript")); // "Hello JavaScript"

• slice(beginIndex, endIndex)

//Extracts a section of a string and returns it as a new string.
const str = "Hello World";
console.log(str.slice(0, 5)); // "Hello"

• split(separator, limit)

//Splits a string into an array of substrings.
const str = "Hello World";
console.log(str.split(" ")); // ["Hello", "World"]

• substring(indexStart, indexEnd)

//Returns a new string containing the characters between two indices.
const str = "Hello World";
console.log(str.substring(0, 5)); // "Hello"

• toLowerCase()

//Returns the string converted to lowercase.
const str = "Hello World";
console.log(str.toLowerCase()); // "hello world"

• toUpperCase()

//Returns the string converted to uppercase.
const str = "Hello World";
console.log(str.toUpperCase()); // "HELLO WORLD"

• trim()

//Removes whitespace from both ends of a string.
const str = " Hello World ";
console.log(str.trim()); // "Hello World"

• startsWith(searchString, position)

//Checks if a string starts with a specified value.
const str = "Hello World";
console.log(str.startsWith("Hello")); // true

• endsWith(searchString, length)

//Checks if a string ends with a specified value.
const str = "Hello World";
console.log(str.endsWith("World")); // true

• padStart(targetLength, padString)

//Pads the current string with another string until the resulting string reaches the given length.
const str = "5";
console.log(str.padStart(4, "0")); // "0005"

• padEnd(targetLength, padString)

//Pads the current string with another string until the resulting string reaches the given length.
const str = "5";
console.log(str.padEnd(4, "0")); // "5000"

• fromCharCode(...codes)

//Converts Unicode values to characters.
console.log(String.fromCharCode(72, 101, 108, 108, 111)); // "Hello"

• at(index)

//Returns the character at a specified index, allowing for negative values.
const str = "Hello";
console.log(str.at(-1)); // "o"

• codePointAt(index)

//Returns a non-negative integer that is the Unicode code point value of the character at the specified index.
const str = "Hello";
console.log(str.codePointAt(0)); // 72

• normalize(form)

//Returns the Unicode Normalization Form of the string.
const str = "e\u0301";
console.log(str.normalize("NFC")); // "é"

• trimStart() or trimLeft()

// Removes whitespace from the beginning of a string.
const str = " Hello World";
console.log(str.trimStart()); // "Hello World"

• trimEnd() or trimRight()

//Removes whitespace from the end of a string.
const str = "Hello World ";
console.log(str.trimEnd()); // "Hello World"