Swift: How to get substring from start to last index of character

Question

I want to learn the best/simplest way to turn a string into another string but with only a subset, starting at the beginning and going to the last index of a character.

Answer 1

In Swift 5

We need String.Index instead of simple Int value to represent Index.

Also remember, when we try to get subString from Swift String (value type), we actually have to iterate with Sequence protocol, which returns String.SubSequence type instead of String type.

To get back String from String.SubSequence, use String(subString)

Example As Below:

    let string = "https://stackoverflow.com"
    let firstIndex = String.Index(utf16Offset: 0, in: string)
    let lastIndex = String.Index(utf16Offset: 6, in: string)
    let subString = String(string[firstIndex...lastIndex])