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. |