如果目标存在，则正则表达式删除前导字符，否则返回整行

Question

我正在使用Notepad ++并需要一个正则表达式来删除目标之前的所有字符（如果存在）。有些线路根本没有目标，在这种情况下我想保持线路不变。

In this example lets use a "<" character:

This line doesn't have one
This line does <keep>
This line also <and we'll keep all this
This line doesn't either
This line <has two< in it

Results:

This line doesn't have one
<keep>
<and we'll keep all this
This line doesn't either
<has two< in it

提前致谢

Answer 1

• 控制 + ħ
• 找到：^.*?(<.*)
• 替换为：$1
• 全部替换

<强>解释

^       : beginig of line
.*?     : 0 or more any character, not greedy
(<.*)   : group 1, '<' followed by 0 or more any character
$       : end of line

• 请勿检查. matches newline

给定示例的结果：

This line doesn't have one
<keep>
<and we'll keep all this
This line doesn't either
<has two< in it

Answer 2

您可以使用/^.*?(?=<)/m代替。

Demo