Top 10 string method in JavaScript you should know

1. charAt():

chartAt() means character at. It returns the character of a index number.

const sentence = 'I love my country';
console.log(`The character at index 3 is ${sentence.charAt(3)}`);
Output:
"The character at index 3 is o"

2. concat():

concat() method concatenates two or more strings together.

const string1 = 'Mashrafe';
const string2 = 'Mortaza';
const addStrings = string1.concat(' ',string2);
console.log(addStrings);
Output: "Mashrafe Mortaza"
const newString = string2.concat(' ',string1);
console.log(newString);
Output: "Mortaza Mashrafe"

3. includes():

This method returns true or false value by case-sensative searching to detect one string in another string.

const sentence = 'I love to play cricket';
const word = 'play';
console.log(sentence.includes(word));
Output: true
const word2 = 'box';
console.log(sentence.includes(word2));
Output: false

4. indexOf():

indexOf() method returns the index number of an string in another string. If the searched string is not found then it returns -1.

const string = "Let's learn string of javascript";
const searchString = 'learn';
console.log(string.indexOf(searchString));
Output: 6
const searchString2 = 'earn';
console.log(string.indexOf(searchString2))
Output: -1

5. replace():

The method replace a string by searching into another string. If the searching string doesn’t match then the main string remain same.

const string = "This is mission escape. Are you ready?";
console.log(string.replace('escape', 'run'));
Output: 
"This is mission run. Are you ready?"

6. slice():

The method does great job. It bring out a section of a string and returns it as a new string. The original string doesn’t modify at all.

const string = 'I am a javascript developer and I love string';
console.log(string.slice(7));
Output:
"javascript developer and I love string"
console.log(string.slice(5, 11));
Output: 
"a java"
console.log(string.slice(-6));
Output: 
"string"
console.log(string.slice(-13, -7));
Output: 
"I love"

7. split():

The method brings out an ordered list of substrings from a string, puts these substrings into an array, and returns the array.

const string = 'I am a javascript developer and I love string';
const words = string.split(' ');
console.log(words[5]);
Output: 
"and"

8. substr():

The method returns a part of the string, starting at the specified index and pervading for a given number of characters afterwards.

const string = 'Mashrafe';
console.log(str.substr(2, 5));
Output: 
"shraf"

9. toLowerCase():

It’s a very fun fact that this method convert all uppercase word to lowercase.

const sentence = 'I am a javascript developer and I love string';
console.log(sentence.toLowerCase());
Output:
"i am a javascript developer and i love string"

10. trim():

This method does a cool fact. It removes whitespace from both ends of a string.

const sentence = ' I am a javascript developer and I love string ';
console.log(sentence.trim());
Output:
"I am a javascript developer and I love string"