Validating regular expression

Question

I have been working with this problem for some time and was hoping for some guidance. I am prompting the user to enter "course" info (example AAA.111#2222_aa-1234 ) I then created a validate function and button for the html page to source from the javascript

Within my isValidInfo function, I can get it to work with:

var infoRegExp = /^(\D{3}.\d{3}#\d{4}_\D{2}-\d{4})$/g;

with the IF statement BUT the else statement does not produce the "Invalid information" message.

Also once I change the code within the function to be case sensitive ie;

/^(\D[A-Z][A-Z][A-Z].\d{3}#\d{4}_\D[a-z][a-z]-\d{4})$/i;

the validate function/button does not work.

<!DOCTYPE html>
<html lang = "en">
    <head>
        <title>Input Course Info</title>
    </head>
    <body>
        <script src = "course.js"></script>
        <button onclick= "validate()">Validate</button>
    </body>

</html>

function isValidInfo(course) {
    var infoRegExp = /^(\D[A-Z][A-Z][A-Z].\d{3}#\d{4}_\D[a-z][a-z]-\d{4})$/i;
    var result = infoRegExp.test(course);
    return result
}
var course = prompt("Enter course information (format: AAA.111#2222_aa-1234): ");
function validate(){
    if (isValidInfo(course)) {
        document.write("Valid information!");
    } else {
        documwnt.write("Invalid information.")
    }
}

I need to be able to click the validate button a produce either a "Valid information!" message or an "Invalid information." message. Any helpful guidance would be appreciated. Right now with the code as is, the validate button does nothing. Removing the [AZ]... and [az] and changing the 'i' to a 'g' gets it to work if I enter aaa.111#2222_aa-1234, but anything ELSE does not produce a message sighting invalid info.

Answer 1

You may use

 function isValidInfo(course) { var infoRegExp = /^[AZ]{3}\\.\\d{3}#\\d{4}_[az]{2}-\\d{4}$/i; // Remove i flag if aaa.111#2222_aa-1234 is invalid! var result = infoRegExp.test(course); return result } var course = prompt("Enter course information (format: AAA.111#2222_aa-1234): "); function validate(){ if (isValidInfo(course)) { return "Valid information!"; } else { return "Invalid information."; } } console.log(validate(course));

The regex demo is available here . Note that validate() function should be called with your course argument, hence I added validate(course) in the console.log() .

Also, see the regex graph :

Details

^ - start of string
[AZ]{3} - three letters (case insensitive modifier makes it match lowercase letters, too)
\\. - a dot
\\d{3} - three digits
# - a # char
\\d{4} - four digits
_ - an underscore
[az]{2} - any 2 letters
- - a hyphen
\\d{4} - four digits (case insensitive modifier makes it match lowercase letters, too)
$ - end of string.

Validating regular expression

Question

1 answers

solution1
2 2019-06-12 16:06:18

Validating regular expression

Question

1 answers

solution1 2 2019-06-12 16:06:18

solution1
2 2019-06-12 16:06:18