remove n lines after matching pattern?

Question

In javascript I am trying to remove 3 lines after matching pattern (including line with matching pattern)

#Guest 
line 1
line 2
line 3

I know how to do it sed , look here. Don't how to translate to javascript

??? data.replace(/.*#Guest.*+5d/g, ''); 

Answer 1

You can use something like this.

^([\s\S]*?)\n#Guest.*(?:\n.*){3}

And replace by $1.See demo.

https://regex101.com/r/rO0yD8/10

var re = /^([\s\S]*?)\n#Guest.*(?:\n.*){3}/g; 
var str = 'sdfdsf\nsdfsdf\nsdf\nsdf\n#Guest\nline 1\nline 2\nline 3\ndsfsdf\nsd\nf\nsd\nf\n';
var subst = '$1'; 

var result = str.replace(re, subst);