Regular Expressions 101

httpthe literal text http (case sensitive)

s?optionally matches the literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

https?

New

# Quantifier：？篇

#下方為測試文字區塊
http://www.kcg.gov.tw/Default.aspx
https://www.google.com.tw/
http://www.gov.taipei/
https://www.youtube.com/?gl=TW
https://www.netflix.com/tw/

＃解釋：藍色部分就是透過規則/https?/所配對成功的文字，這裡判斷說http後，如果有 s 代表配對成功，沒有 s 也可以判斷成功。

Regular Expression

Substitution