JavaScript String Reference
JavaScript Strings
A JavaScript string stores a series of characters like "John Doe".
A string can be any text inside double or single quotes:
var carname = "Volvo XC60";
var carname = 'Volvo XC60';
String indexes are zero-based: The first character is in position 0, the second in 1, and so on.
For a tutorial about Strings, read our JavaScript String Tutorial.
String Properties and Methods
Primitive values, like "John Doe", cannot have properties or methods (because they are not objects).
But with JavaScript, methods and properties are also available to primitive values, because JavaScript treats primitive values as objects when executing methods and properties.
String Properties
Property | Description |
---|---|
constructor | Returns the string's constructor function |
length | Returns the length of a string |
prototype | Allows you to add properties and methods to an object |
String Methods
Method | Description |
---|---|
charAt() | Returns the character at the specified index (position) |
charCodeAt() | Returns the Unicode of the character at the specified index |
concat() | Joins two or more strings, and returns a new joined strings |
endsWith() | Checks whether a string ends with specified string/characters |
fromCharCode() | Converts Unicode values to characters |
includes() | Checks whether a string contains the specified string/characters |
indexOf() | Returns the position of the first found occurrence of a specified value in a string |
lastIndexOf() | Returns the position of the last found occurrence of a specified value in a string |
localeCompare() | Compares two strings in the current locale |
match() | Searches a string for a match against a regular expression, and returns the matches |
repeat() | Returns a new string with a specified number of copies of an existing string |
replace() | Searches a string for a specified value, or a regular expression, and returns a new string where the specified values are replaced |
search() | Searches a string for a specified value, or regular expression, and returns the 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 the characters from a string, beginning at a specified start position, and through the specified number of character |
substring() | Extracts the characters from a string, between two specified indices |
toLocaleLowerCase() | Converts a string to lowercase letters, according to the host's locale |
toLocaleUpperCase() | Converts a string to uppercase letters, according to the host's locale |
toLowerCase() | Converts a string to lowercase letters |
toString() | Returns the value of a String object |
toUpperCase() | Converts a string to uppercase letters |
trim() | Removes whitespace from both ends of a string |
valueOf() | Returns the primitive value of a String object |
All string methods return a new value. They do not change the original variable.
String HTML Wrapper Methods
The HTML wrapper methods return the string wrapped inside the appropriate HTML tag.
These are not standard methods, and may not work as expected in all browsers.
Method | Description |
---|---|
anchor() | Creates an anchor |
big() | Displays a string using a big font |
blink() | Displays a blinking string |
bold() | Displays a string in bold |
fixed() | Displays a string using a fixed-pitch font |
fontcolor() | Displays a string using a specified color |
fontsize() | Displays a string using a specified size |
italics() | Displays a string in italic |
link() | Displays a string as a hyperlink |
small() | Displays a string using a small font |
strike() | Displays a string with a strikethrough |
sub() | Displays a string as subscript text |
sup() | Displays a string as superscript text |