exec( )

It's used to find the first match

• Also used when having more than 9 '(x)' (group patterns) are used & have to access them individually
• It also modifies the 'lastIndex' property value as match found

Syntax

library_booksRegExPattern.exec(string)

Syntax- To find the length

library_booksRegExPattern.exec(string).length

Syntax- To access via index value

library_booksRegExPattern.exec(string)[index]  // index starts from 0

For example :

library_booksvar str="This Is a book";
var pattern=/is/ig;
alert(pattern.exec(str));
// Output: is

Matches: This Is a book

Comment : Returns the first match ('is' in above case)

Example : having more than 9 '(x)' (group patterns) are used

library_booksvar str="111213141516171819202122232425";
var pattern=/(..)(..)(..)(..)(..)(..)(..)(..)(..)(..)../;
var all=pattern.exec(str);
alert(all);
// Output: 1112131415161718192021,11,12,13,14,15,16,17,18,19,20
alert(all[0]);
// Output: 1112131415161718192021
alert(all[1]);
// Output: 11
alert(all[10]);
// Output: 20

Matches: 111213141516171819202122232425

Comment : Returns the first match & all the '(x)' patterns value, you can access them individually via their index

test( )

It's used to check for a match available in a string or not & returns true or false

• It also modifies the 'lastIndex' property value as match found

Syntax

library_booksRegExPattern.test(string)

For example :

library_booksvar str="This Is a book";
var pattern=/is/ig;
alert(pattern.test(str));
// Output: true

Comment : Check, match found or not ('true' in above case)

toString( )

It's used to get the string value of the regular expression

Syntax

library_booksRegExPattern.toString()

For example :

library_booksvar str="This Is a book";
var pattern=/is/ig;
alert(pattern.toString());
// Output: /is/ig

Comment : Returns the string value of the pattern ('/is/ig' in above case)