正则表达式替换除＃和@之外的所有符号

Question

I am not super confident with using regexp, but my end goal is to have something that is removing all symbols excluding @ and #.

What I have now is [\\p{P}\\d]. It works fine but it also removes @ and # which I need to keep.

Here is the sample input string:

^Hello, my #friend @Даниил%% 中英 字 典!!.

that I am trying to change into

Hello my #friend @Даниил 中英 字 典

Answer 1

Capture the symbols you need to keep and replace with $1 backreference to restore the captured part in the resulting string:

package main

import (
    "fmt"
    "regexp"
)

func main() {
    s := "^Hello, my #friend @Даниил%% 中英 字 典!!."
    re := regexp.MustCompile(`([#@])|[\p{P}\p{S}\d]`)
    s = re.ReplaceAllString(s, "$1")
    fmt.Println(s)
}

See this Go demo printing Hello my #friend @Даниил 中英 字 典.

Note that ^ does not belong to the \p{P} category, thus, I added \p{S} one.

The pattern is ([#@])|[\p{P}\p{S}\d], see its online demo.

Details:

• ([#@]) - Capturing group 1 (referred to with $1 / ${1} from the replacement pattern) matching a # or @
• | - or
• [\p{P}\p{S}\d] - a punctuation, symbol or digit char.