How to extract phrase from string using Range? [duplicate] - ios

Question

This question already has answers here:
Finding index of character in Swift String
(33 answers)
Closed 6 years ago.
This sounds easy, but I am stumped. The syntax and functions of Range are very confusing to me.
I have a URL like this:
https://github.com/shakked/Command-for-Instagram/blob/master/Analytics%20Pro.md#global-best-time-to-post
I need to extract the part #global-best-time-to-post, essentially the # to the end of the string.
urlString.rangeOfString("#") returns Range
Then I tried doing this assuming that calling advanceBy(100) would just go to the end of the string but instead it crashes.
hashtag = urlString.substringWithRange(range.startIndex...range.endIndex.advancedBy(100))

Answer 1

Easiest and best way to do this is use NSURL, I included how to do it with split and rangeOfString:
import Foundation
let urlString = "https://github.com/shakked/Command-for-Instagram/blob/master/Analytics%20Pro.md#global-best-time-to-post"
// using NSURL - best option since it validates the URL
if let url = NSURL(string: urlString),
fragment = url.fragment {
print(fragment)
}
// output: "global-best-time-to-post"
// using split - pure Swift, no Foundation necessary
let split = urlString.characters.split("#")
if split.count > 1,
let fragment = split.last {
print(String(fragment))
}
// output: "global-best-time-to-post"
// using rangeofString - asked in the question
if let endOctothorpe = urlString.rangeOfString("#")?.endIndex {
// Note that I use the index of the end of the found Range
// and the index of the end of the urlString to form the
// Range of my string
let fragment = urlString[endOctothorpe..<urlString.endIndex]
print(fragment)
}
// output: "global-best-time-to-post"

Answer 2

You could also use substringFromIndex
let string = "https://github.com..."
if let range = string.rangeOfString("#") {
let substring = string.substringFromIndex(range.endIndex)
}
but I'd prefer the NSURL way.

Answer 3

use componentsSeparatedByString method
let url = "https://github.com/shakked/Command-for-Instagram/blob/master/Analytics%20Pro.md#global-best-time-to-post"
let splitArray = url.componentsSeparatedByString("#")
your required last text phrase (without # char) will be at the last index of the splitArray , you can concatenate the # with your phrase
var myPhrase = "#\(splitArray[splitArray.count-1])"
print(myPhrase)