Regular Expressions 101

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  • Unit Tests (8)
/
^[a-zA-Z]+[\'-]{0,1}[a-zA-Z]+$
/
i
^ asserts position at start of the string
Match a single character present in the list below
[a-zA-Z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case insensitive)
Match a single character present in the list below
[\'-]
{0,1} matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\' matches the character ' with index 3910 (2716 or 478) literally (case insensitive)
- matches the character - with index 4510 (2D16 or 558) literally (case insensitive)
Match a single character present in the list below
[a-zA-Z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
A-Z matches a single character in the range between A (index 65) and Z (index 90) (case insensitive)
$ asserts position at the end of the string, or before the line terminator right at the end of the string (if any)
Global pattern flags
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
i

Test String