Replacing a swift String with another string at a specific index

Question

Lets say I have a Swift string

"Hello I'm John Doe"

I want to replace John Doe with:

Steve.

How is that done with Swift 3? The syntax is taking me forever to figure out.

I've tried a few things, one of them is x.replaceSubrange, but it has a syntax that I'm not able to figure out.

x?.replaceSubrange(<#T##bounds: Range##Range#>, with: <#T##String#>)

I tried to create a range with NSRange, but it didn't like that either.

What's so hard? `string.replacingOccurrences(of: "John Doe", with: "Steve")` — Leo Dabus, May 29 '17 at 15:35
John doe can be Mary doe. but I want to replace using an index after "I'm" — mskw, May 29 '17 at 15:36
The the thing is, even "Hello I'm" can be "Hi I'm" it is dynamic. It is just an example, but I need to use ranges for my example. It's a UITextField replacement thing. — mskw, May 29 '17 at 15:38
So you don't even know if the guy's (maybe compound) name has 1, 2, 3 or even more. How are you dealing with it? — Leo Dabus, May 29 '17 at 15:40
You should have a placeholder for name there, e.g. `$name`. All other solutions are easy to break with non-standard names. The problem is not finding the start of the name but the end of it. — Sulthan, May 29 '17 at 15:41
@LeoDabus, the uitextFieldDelegate gives me the range, but it uses NSRange. — mskw, May 29 '17 at 15:42
Compare [NSRange to Range](https://stackoverflow.com/q/25138339/2976878) — Hamish, May 29 '17 at 15:45

score 1 · Answer 1 · answered May 29 '17 at 15:42

1

So you want to remove the substring after I'm and then append another string.

let original = "Hello I'm John Doe"
let marker = "I'm"
let newName = "Steve"

guard let startIndex = original.range(of: marker) else { fatalError() }
let result = "\(original.substring(with: startIndex)) \(newName)

// "I'm Steve"

answered May 29 '17 at 15:42

Luca Angeletti

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Thats not the question here – Leo Dabus May 29 '17 at 15:44

TedMeftah · Accepted Answer · 2017-05-29T16:21:09.780

0

let s1 = "Hello I'm John Doe"

//Get the start of `John Doe`
if let index = s1.range(of: "John Doe", options: .literal) {
    // Take the string from start until `John Doe` append `Steve.` to it
    let s2 = s1.substring(to: index.lowerBound).appending("Steve.")
}

edited May 29 '17 at 16:21

answered May 29 '17 at 15:38

TedMeftah

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This works, but not what I'm looking for, but given my question seem a bit ambiguous, this is the most correct one. – mskw May 29 '17 at 18:05

Replacing a swift String with another string at a specific index

2 Answers2