How to judge characters by using regular expressions

This article introduces you how to use regular expressions to judge characters, the content is very detailed, interested friends can use for reference, I hope it can be helpful to you.

If the given string is a palindrome, true is returned, and vice versa, false is returned.

If a string ignores punctuation, case, and spaces and reads it exactly the same as reading it backwards, then the string is palindrome.

Note that you need to remove extra punctuation marks and spaces from the string, and then convert the string to lowercase to verify that the string is a palindrome.

The values of function parameters can be "racecar", "RaceCar" and "race CAR".

Key code:

Remove punctuation and white space from the string. You can use str.replace () + regular expression matching.

Var newStr = str.replace (/ [\ |\ ~ | `|\! |\ @ |\ # |\ $|\% |\ ^ |\ * |\ (|\) |\-|\ _ |\ = |\ | |\ [|\] |\ {|\} |\; |\: |\ |\'|\, |\ |\ / |\] / g, ""))

The complete code is as follows:

Function palindrome (str) {/ / Good luckroomvar newStr = str.replace (/ [\ |\ ~ | `|\! |\ @ |\ $|\% |\ ^ |\ * |\ * |\-|\ + |\ = |\ [|\] |\ {|\} |\;\: |\ "|\'|\,\ |\ |\ / |\] / g,"); var newNewStr = newStr.toLowerCase () / / convert to lowercase var spl = newNewStr.split (""); / / split the string into an array var newSpl = spl.reverse (); / / flip var newRel = newSpl.join (""); / / convert again to the string if (newNewStr = = newRel) {/ / compare return true;} else return false;} palindrome ("eye") On the use of regular expressions on how to judge characters to share here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.