Javascript Essentials: Strings (CheatSheet)

In JavaScript, a string is a sequence of characters enclosed in single or double quotes. For example, you can create a string with the following code:

const myString = "This is my string";

Strings are commonly used in JavaScript to store and display text. You can use string methods to manipulate and work with strings, such as getting the length of a string or concatenating (joining) two or more strings together.Strings can be created as primitives, from string literals, or as objects, using the String() constructor:

const string4 = new String("A String object");

String Methods:

• charAt() Returns the character at a specified index (position)
• charCodeAt() Returns the Unicode of the character at a specified index
• concat() Returns two or more joined strings
• endsWith() Returns if a string ends with a specified value
• fromCharCode() Returns Unicode values as characters
• includes() Returns if a string contains a specified value
• indexOf() Returns the index (position) of the first occurrence of a value in a string
• lastIndexOf() Returns the index (position) of the last occurrence of a value in a string
• localeCompare() Compares two strings in the current locale
• match() Searches a string for a value, or a regular expression, and returns the matches
• repeat() Returns a new string with a number of copies of a string
• replace() Searches a string for a value, or a regular expression, and returns a string where the values are replaced
• search() Searches a string for a value, or regular expression, and returns the index (position) of the match
• slice() Extracts a part of a string and returns a new string
• split() Splits a string into an array of substrings
• startsWith() Checks whether a string begins with specified characters
• substr() Extracts a number of characters from a string, from a start index (position)
• substring() Extracts characters from a string, between two specified indices (positions)
• toLocaleLowerCase() Returns a string converted to lowercase letters, using the host’s locale
• toLocaleUpperCase() Returns a string converted to uppercase letters, using the host’s locale
• toLowerCase() Returns a string converted to lowercase letters
• toString() Returns a string or a string object as a string
• toUpperCase() Returns a string converted to uppercase letters
• trim() Returns a string with removed whitespaces
• valueOf() Returns the primitive value of a string or a string object