How can I search for a String and get an Index where I can produce for example a new String/Substring with e.g:
dfnaseurewruTESTAB=41201243
so that in this example I can search for TESTAB and produce a new String:
TESTAB=41201243
2 Answers
You can't really do it in pure Swift, which (amazingly) lacks the ability to search for substrings. You have to operate in the presence of Foundation; that way, you can use Cocoa's range(of:). The result is translated from an NSRange back into a Swift Range for you (wrapped in an Optional in case the substring isn't present at all). The lower bound of the range is the index you're looking for — the start of the substring.
let s = "dfnaseurewruTESTAB=41201243"
if let r = s.range(of: "TESTAB") {
let s2 = s.suffix(from: r.lowerBound)
print(s2) // "TESTAB=41201243"
}
Comments
You can using Regular Expression for find your TESTAB=number string
Regular Expression can be
TESTAB=[\d]+
with TESTAB is your string, = to find the number after and [\d]+ is has one or more number
For example, in Swift 4.1
let regex = "TESTAB=[\\d]+"
let string = "dfnaseurewruTESTAB=41201243"
if let range = string.range(of: regex, options: .regularExpression, range: nil, locale: nil) {
print(string[range]) // result is TESTAB=41201243
}
