regular expression to match a ascii character - regex

Question

I want to match a regular expression for the string
2=abc\u000148=123\u0001
Explanation
Key value pairs separated by SOH(\u0001) characeter
Key - Number
Value can be string of number ,alphabets,decimals
key and value are separated by "="
The regex I tried is
[0-9]=.*[u0001]+
but it does not matches properly
Update
I have a list of numbers val num =Seq(2,3,4)
Instead of finding I want to remove the matches from the string
keys for which I want to replace is from values inside list num
Input
2=abc\u000148=123\u00013=def\u0001
Output It is the filtered string
148=123\u0001 ,where keys which match value 2 and 3 are removed from list
object Main extends App {
val s = "2=abc\u000148=123\u00013=def\u0001"
val num = Seq(2,3)
for (e <- num) {
val p = s"(\\$e+)=([^\u0001]*)".r
test(p)
}
private def test(p: Regex) = {
p.findAllIn(s).matchData foreach {
m => println(m.group(1) + " : " + m.group(2))
}
}
}

Answer 1

You need to build the pattern dynamically like this:
s"\\b(?:${num.mkString("|")})=[^\\u0001]*\\u0001*"
Details
\b - a word boundary
(?:num1|num2...|numN) - any of the values in the num variable
= - an equal sign
[^\u0001]* - zero or more chars other than a SOH char (a char with the decimal code of 1)
\u0001* - zero or more SOH chars.
See a Scala demo:
val num = Seq(2,3)
val s = "1041=pqr\u000148=xyz\u000122=8\u00012=abc\u000148=123\u00013=def\u0001"
val pattern = s"\\b(?:${num.mkString("|")})=[^\\u0001]*\\u0001*"
// println(pattern) // => \b(?:2|3)=[^\u0001]*\u0001*
println(s.replaceAll(pattern, ""))
// => 1041=pqr\u000148=xyz\u000122=8\u000148=123\u0001