使用Java RegEx删除配对主题标签之间的内容##

Question

在Java中，使用正则表达式仅在配对哈希标签中删除内容有更快的方法吗？ 我会举一些例子：

When user logs in ## //Expected Result: When user logs in ## 
When user logs in # //Expected Result: When user logs in # 
When user logs in #the system# //Expected Result: When user logs in ## 
When user logs in #the system //Expected Result: When user logs in #the system 
When user logs in #the system# named #test //Expected Result: When user logs in ## named #test 

我见过的例子删除括号中的内容，但，这是因为一点点不同“（”和“）”是不同的字符，如果我只是使用replace，编译器不能到#the system#和#test

Answer 1

之间

区分内容您可以使用：

str = str.replaceAll("(?!<#)#[^#]+#(?!#)", "##); 

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