正則表達式：檢查`abc`然後`在

Question

之間如何使用正則表達式查找所有以abc開始，與def結束，但不包含在兩者之間123字符串，不`123` def`？

Answer 1

您可以在這裏使用Negative Lookahead。

^abc(?:(?!123).)*def$ 

正則表達式

^    # the beginning of the string 
abc   # 'abc' 
(?:   # group, but do not capture (0 or more times) 
(?!   # look ahead to see if there is not: 
    123   # '123' 
)    # end of look-ahead 
.    # any character except \n 
)*    # end of grouping 
def   # 'def' 
$    # before an optional \n, and the end of the string