find last index of a string in swift

Question

In swift 4 you can use the following method to extract a substring:

let str = "abcdefghci"
let index = str.index(of: "c") ?? str.endIndex
print(str[...index])

This will print abc

But how can I find the index of the last c, to extract a substring from that location ?

UPDATE
@vadian please see the attached image:

score 5 · Accepted Answer · answered Jun 19 '18 at 08:37

5

Use range(of which can search backwards and use lowerBound as end index.

let str = "abcdefghci"
if let range = str.range(of: "c", options: .backwards)  {
    print(str[...range.lowerBound])
}

answered Jun 19 '18 at 08:37

vadian

I am getting the following error: `Value of type 'String' has no member 'range'` – nshathish Jun 20 '18 at 05:44
The code snippet must not throw an error. – vadian Jun 25 '18 at 09:04
please see my update to the post, and I've attached an image to show what error I am getting – nshathish Jun 26 '18 at 11:15
You need to `import Foundation` in the Playground – vadian Jun 26 '18 at 11:19
thanks-it solved it – nshathish Jul 03 '18 at 07:42
I get Subscript 'subscript(_:)' requires the types 'String.Index' and 'Int' be equivalent error – chitgoks Aug 28 '22 at 23:47
1

@chitgoks My answer doesn't contain any `Int` index, but it seems that you try to subscript an array with an `Int` index. This is not possible. – vadian Aug 29 '22 at 04:56

1 Answers1