A JavaScript String object represents a sequence of characters.
How to create a Javascript string object:
1. By using string literals.
2. By using String() constructor.
By using string literals:
When we create a string literal browser automatically converts it to a String object.
Syntax:
var string1 = “value”;
Example:
<!DOCTYPE html> <html> <body> <script> var string1="String example by string literal."; document.write(string1); </script> </body> </html>
Try it:
By using String() constructor:
We can create a JavaScript String object by using the String() constructor.
Syntax:
var string1 = new String(value);
Example:
<!DOCTYPE html> <html> <body> <script> var string1=new String("String example by String constructor."); document.write(string1); </script> </body> </html>
Try it:
JavaScript String Object Properties:
Property | Description |
constructor | It returns a reference to the String function that created the object. |
length | It returns the length of the string. |
prototype | It allows us to add properties and methods to an object. |
JavaScript String Object Methods:
Method | Description |
charAt() | It returns the character at the specified index. |
charCodeAt() | It returns a number indicating the Unicode value of the character at the given index. |
concat() | It combines the text of two strings and returns a new string. |
indexOf() | It returns the index within the calling String object of the first occurrence of the specified value, or -1 if not found. |
lastIndexOf() | It returns the index within the calling String object of the last occurrence of the specified value, or -1 if not found. |
match() | It is used to match a regular expression against a string. |
replace() | It is used to find a match between a regular expression and a string and to replace the matched substring with a new substring. |
search() | It executes the search for a match between a regular expression and a specified string. |
slice() | It extracts a section of a string and returns a new string. |
substr() | It returns the characters in a string beginning at the specified location through the specified number of characters. |
substring() | It returns the characters in a string between two indexes into the string. |
toLowerCase() | It returns the calling string value converted to lowercase. |
toLocaleLowerCase() | The characters within a string are converted to lowercase while respecting the current locale. |
toUpperCase() | It returns the calling string value converted to uppercase. |
toLocaleUpperCase() | The characters within a string are converted to upper case while respecting the current locale. |
toString() | It returns a string representing the specified object. |
valueOf() | It returns the primitive value of the specified object. |