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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

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
229,607 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.