test method in JavaScript regular expressions
In this lesson, we will look at the
test method, which checks if
a string contains at least one match
with a regex. If there is, true
is returned, and if not, false.
The method takes a string as a parameter,
and is applied to a regex, like this:
javascriptregex.test(where to search)
For example, let's check some string for compliance with a regex:
javascript/a+/.test('eee aaa bbb'); // returns true
Often this method is used to check if a regular expression matches an entire string. In this case, at the beginning of the regex they put a hat, and at the end - a dollar:
javascript/^a+$/.test('aaaaaaaaa'); // returns true
Determine whether a passed string
starts with 'http://'.
Determine whether a passed string
begins with 'http://' or
'https://'.
Determine whether a passed string
ends with the extension 'txt',
'html', or 'php'.
Determine whether a passed string ends
with the extension 'jpg' or
'jpeg'.
Determine whether a passed string ends
with the extension 'jpg',
'jpeg', or 'png'.
Determine whether a passed string is
'a number having from 1 to
12 digits'.
Determine whether a passed string is a date in the year-month-day format.
Determine whether a passed string is a date in the day.month.year format.
Determine whether a passed string is a time in the hours:minutes:seconds format.
Determine whether a passed string is a valid email.
Determine whether a passed string is a domain name.