Splitting a string in swift using multiple delimiters
Swift 4.2 update to @vir us's answer:
let string = "dots.and-hyphens"
let array = string.components(separatedBy: CharacterSet(charactersIn: ".-"))
This isn't very efficient, but it should do the job:
import Foundation
extension String {
func componentsSeperatedByStrings(ss: [String]) -> [String] {
let inds = ss.flatMap { s in
self.rangeOfString(s).map { r in [r.startIndex, r.endIndex] } ?? []
}
let ended = [startIndex] + inds + [endIndex]
let chunks = stride(from: 0, to: ended.count, by: 2)
let bounds = map(chunks) { i in (ended[i], ended[i+1]) }
return bounds
.map { (s, e) in self[s..<e] }
.filter { sl in !sl.isEmpty }
}
}
"KEY1=subKey1=value&subkey2=valueKEY2=subkey1=value&subkey2=valueKEY3=subKey1=value&subkey3=value".componentsSeperatedByStrings(["KEY1", "KEY2", "KEY3"])
// ["=subKey1=value&subkey2=value", "=subkey1=value&subkey2=value", "=subKey1=value&subkey3=value"]
Or, if you wanted it in dictionary form:
import Foundation
extension String {
func componentsSeperatedByStrings(ss: [String]) -> [String:String] {
let maybeRanges = ss.map { s in self.rangeOfString(s) }
let inds = maybeRanges.flatMap { $0.map { r in [r.startIndex, r.endIndex] } ?? [] }
let ended = [startIndex] + inds + [endIndex]
let chunks = stride(from: 0, to: ended.count, by: 2)
let bounds = map(chunks) { i in (ended[i], ended[i+1]) }
let values = bounds
.map { (s, e) in self[s..<e] }
.filter { sl in !sl.isEmpty }
let keys = filter(zip(maybeRanges, ss)) { (r, _) in r != nil }
var result: [String:String] = [:]
for ((_, k), v) in zip(keys, values) { result[k] = v }
return result
}
}
"KEY1=subKey1=value&subkey2=valueKEY2=subkey1=value&subkey2=valueKEY3=subKey1=value&subkey3=value".componentsSeperatedByStrings(["KEY1", "KEY2", "KEY3"])
// ["KEY3": "=subKey1=value&subkey3=value", "KEY2": "=subkey1=value&subkey2=value", "KEY1": "=subKey1=value&subkey2=value"]
For Swift 2:
import Foundation
extension String {
func componentsSeperatedByStrings(ss: [String]) -> [String] {
let unshifted = ss
.flatMap { s in rangeOfString(s) }
.flatMap { r in [r.startIndex, r.endIndex] }
let inds = [startIndex] + unshifted + [endIndex]
return inds.startIndex
.stride(to: inds.endIndex, by: 2)
.map { i in (inds[i], inds[i+1]) }
.flatMap { (s, e) in s == e ? nil : self[s..<e] }
}
}
One can also use the following approach to split a string with multiple delimiters in case keys are single characters:
//swift 4+
let stringData = "K01L02M03"
let res = stringData.components(separatedBy: CharacterSet(charactersIn: "KLM"))
//older swift syntax
let res = stringData.componentsSeparatedByCharactersInSet(NSCharacterSet(charactersInString: "KLM"));
res
will contain ["01", "02", "03"]
If anyone knows any kind of special syntax to extend the approach to multiple characters per key you are welcome to suggest and to improve this answer