String, substring, Range, NSRange in Swift 4

Question

I am using the following code to get a String substring from an NSRange:

func substring(with nsrange: NSRange) -> String? {
             


        

Answer 1

With Swift 4 we can get substrings this way.

1. Substring from index

   let originStr = "Test"
   let offset = 1
   let str = String(originStr.suffix(from: String.Index.init(encodedOffset: offset)))
   

2. Substring to index

   let originStr = "Test"
   let offset = 1
   String(self.prefix(index))