//比如\ [] " ' 以[]为例
var ch="微笑";
var str="[微笑]我是小仙女！[微笑]我是小仙女！";alert(str.replace(ch,"哈")); //输出 哈我是小仙女！[微笑]我是小仙女！var encode=eval("/"+"\\["+ch+"\\]"+"/g");alert(str.replace(encode,"哈"));  //输出 哈我是小仙女！哈我是小仙女！

https://blog.csdn.net/weixin_38792911/article/details/108870502#:~:text=%E5%B8%B8%E9%87%8F%E5%85%A8%E5%B1%80%E6%9B%BF%E6%8D%A2%20var%20str%20%3D%22%E6%88%91%E6%98%AF%E6%88%91%E6%98%AF%E6%88%91%E6%98%AF%E5%B0%8F%E4%BB%99%E5%A5%B3%EF%BC%81%20%22%3B,alert%28str.replace%28%22%E6%88%91%E6%98%AF%22%2C%22%E5%93%88%E5%93%88%E5%93%88%22%29%29%3B%20%2F%2F%E8%BE%93%E5%87%BA%20%E5%93%88%E5%93%88%E5%93%88%E6%88%91%E6%98%AF%E6%88%91%E6%98%AF%E5%B0%8F%E4%BB%99%E5%A5%B3%EF%BC%81%20alert%28str.replace%28%2F%E6%88%91%E6%98%AF%2Fg%2C%22%E5%93%88%E5%93%88%E5%93%88%22%29%29%3B%20%2F%2F%E8%BE%93%E5%87%BA%20%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%93%88%E5%B0%8F%E4%BB%99%E5%A5%B3%EF%BC%81