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JavaScript Regular Expressions in JavaScript Validating a Form Validating an Email

Begana Choi
PLUS
Begana Choi
Courses Plus Student 13,126 Points
Posted by Begana Choi
Begana Choi
Courses Plus Student 13,126 Points

why do we use case insensitive for /^[^@]+@[^@.]+\.[a-z]+$/i.test(email); ?

I think I don't understand exactly about case insensitive. I need some more examples to understand it except the examples on video!

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Since email addresses can contain upper and/or lower case, using case insensitivity makes it simpler to construct a pattern. For example, by itself, "[a-z]" would only match lower-case. So "us" would pass, but "US" would not. Making it case-insensitive allows both to pass.

Of course, you could also explicitly specify the pattern as "[A-Za-z]", but that's more verbose.