Javascript regexp: replace this or that word (have or not whitespaces between words)

Question

I have a string which contains multiple words. I have a phrase that should be replaced. However, there are multiple very similar phrases that should be replaced.

Here are strings that should be replaced (removed):

"fox jumps over the lazy dog"
"fox jumps over the lazy cat"
"fox jumpa over the lazy cat"
"fox jumpaoverthe lazy cat" (meaning there could be missing spaces between words)
case insensitive, global

var str = "The quick brown fox jumpa over the lazy dog"; // result would be "The quick brown "

str = "The quick brown fox jump over the lazy dog"; // result would be "The quick brown "

str = "The quick brown fox jump over the lazy cat"; // result would be "The quick brown "

str = "The quick brown fox jumpa over the lazy cat"; // result would be "The quick brown "

str = "The quickbrownfoxjumpaoverthe lazy cat"; // result would be "The quick brown "

My try doesn't work:

    let str1 = "The quick brown fox jumpa overthe lazy cat";
    let reg = /The\s*quick\s*brown\s*fox\s*jump[s|a]\s*over\s*the\s*lazy [\bcat\b|\bdog\b]/gi;
    let res = str1.replace(reg, "");
    console.log(res); //should be empty

    str1 = "The quickbrownfox jumps overthe lazy cat";
    res = str1.replace(reg, "");
    console.log(res); //should be empty

Hassan Imam Hassan Imam · Accepted Answer · 2018-02-01T10:52:41

You can use the following regex : The\s*quick\s*brown\s*fox\s*jump(s|a)?\s*over\s*the\s*lazy\s*(cat|dog)/gi

let str1 = "The quick brown fox jumpa overthe lazy cat";
let reg = /The\s*quick\s*brown\s*fox\s*jump(s|a)?\s*over\s*the\s*lazy\s*(cat|dog)/gi;
let res = str1.replace(reg, "");
console.log(res); //should be empty

str1 = "The quickbrownfox jumps overthe lazy cat";
res = str1.replace(reg, "");
console.log(res); //should be empty

Javascript regexp: replace this or that word (have or not whitespaces between words)

1 Answers