Call Substring multiple times

Question

I have a string and I want to remove this data like this \(f(x) = (a+b)\)
so i am thinking to get all subsstring and then make some operation on array. But it is giving me only one stripedHtml. So not able to get how to clean it. Just wants to remove this equations.

Result will be : Here’s the evidence

const filter_data = `<p>\(f(x) = (a+b)\)</p><p>\(f(x) = (a+db)\)</p><p>\(f(x) = (a+d+c+b)\)</p>
    <p>Here’s the evidence.</p>`
var strippedHtml = filter_data.substring(
  filter_data.lastIndexOf("\(") + 1,
  filter_data.lastIndexOf("\)")
);


console.log(strippedHtml)

Backslash is an escape character. There isn't an actual backslash at index = 3. https://stackoverflow.com/a/3903661/3082296 — adiga, Jan 11 '22 at 12:52
@adiga but these regex are not deleting data between two strings of first string = "\\(" 2nd string = "\\)" — Rambler, Jan 11 '22 at 12:55
I made you a snippet - I had to fix several typos. Please take more care in asking and posting code — mplungjan, Jan 11 '22 at 13:08

score 1 · Answer 1 · answered Jan 11 '22 at 13:23

JS has a replace method for this that accepts RegExp:

const filter_data = `<p>\(f(x) = (a+b)\)</p><p>\(f(x) = (a+db)\)</p><p>\(f(x) = (a+d+c+b)\)</p>
    <p>Here’s the evidence.</p>`;
var strippedHtml = filter_data.replace(/\<.*?\(.*?>/g, "");

console.log(strippedHtml);

The RegExp searches for an < followed by a ( and then an > and replaces all appearances with an empty value.

In your string it will match two times and do a replace. Maybe you have to modify the RegExp to fit your real string as it would also match text nodes containing ( but that's what I would do at this point with the given data.

Thanhal P A · Answer 2 · 2022-01-12T09:22:32.223

1

You can use following regular expressions to obtain solution for only similar type of data you were provided

const filterData1 = `<p>\(f(x) = (a+b)\)</p><p>\(f(x) = (a+db)\)</p><p>\(f(x) = (a+d+c+b)\)</p><p>Here’s the evidence.</p>`
const filterData2 = `<p>\(f(x) = (a+b)\)</p><p>\(f(x) = (a+db)\)</p><p>\(f(x) = (a+d+c+b)\)</p><p>Here’s the evidence.</p><p>\(f(x) = (a+b)\)</p>`

const regEx1 = /<[^>]*>/g   //regular expression to remove all html tags
const regEx2 = /\([^\)]*\)/g  //regular expression to remove everything between \( and \)
const regEx3 = /[=)]/g  //regular expression to remove = and )

const result1 = filterData1.replace(regEx1,'').replace(regEx2,'').replace(regEx3,'').trim()
const result2 = filterData2.replace(regEx1,'').replace(regEx2,'').replace(regEx3,'').trim()

console.log("Result1 : ",result1);
console.log("Result2 : ",result2);

edited Jan 12 '22 at 09:22

answered Jan 11 '22 at 13:29

Thanhal P A

4,097
3
18
38

Hi @Thanhal this regex is failing if data also available between any /( like `
\(f(x) = (a+b)\)
\(f(x) = (a+db)\)
Here’s the evidence.
\(f(x) = (a+d+c+b)\)
– Rambler Jan 11 '22 at 15:06
1

HI @Rambler , I couldn't find any proper way to obtain the solution, but did an update to above answer which will only work with data like you provided above – Thanhal P A Jan 12 '22 at 09:18
Hi @Thanhal this is also. Will try to find next level solution but for now this also good. – Rambler Jan 13 '22 at 04:37

Call Substring multiple times

2 Answers2