How do I search for a range of Strings

Question

How do I search for a range of Strings, I want to search userID

But userID may this time is "123", next time is "zxvcvb", so i can't use offsetBy

let userID = "12345"
let URL = "http://test/main/?Username=\(userID)#!/index.php"
let firstIndex = URL.index(of: "=")
let secondIndex = URL.index(of: "#")
let range = firstIndex...secondIndex //error

technerd · Accepted Answer · 2018-02-27T04:38:12.323

0

Try this code :

let userID = "jshjdschd"
let url = "http://test/main/?Username=\(userID)#!/index.php"

    guard let firstIndex = url.index(of: "="),
        let secondIndex = url[firstIndex...].index(of: "#") else{
            print("UserId not found")
    }

let range = url.index(after: firstIndex)..<secondIndex
let mySubstring = url[range]
print(mySubstring) //jshjdschd

edited Feb 27 '18 at 04:38

answered Feb 27 '18 at 04:16

technerd

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Note that `URL` is a native type. It is Swift naming convention to name the variables starting with a lowercase letter. Btw this would crash the app if the characters are found in the wrong order. You can avoid the crash searching the substring `url[firstIndex...].index(of: "#")` – Leo Dabus Feb 27 '18 at 04:23
@LeoDabus : My mistake, I just take code from question. Updated. Thanks – technerd Feb 27 '18 at 04:27
Btw instead of dropping the first letter just use the index after the firstIndex. `let range = url.index(after: firstIndex).. – Leo Dabus Feb 27 '18 at 04:33
@LeoDabus: I was searching for this solution. Thanks – technerd Feb 27 '18 at 04:37
you are welcome – Leo Dabus Feb 27 '18 at 04:38
1

you are real nerd. Thanks – technerd Feb 27 '18 at 04:38

score 0 · Answer 2 · answered Feb 27 '18 at 04:20

You can use a regex to get the range of the user ID between those two strings:

let userID = "12345"
let pattern = "(?<=Username=)(.*)(?=#!)"
let link = "http://test/main/?Username=\(userID)#!/index.php"
if let range = link.range(of: pattern, options: .regularExpression) {
     let id = link[range]
     print("id:", id)    // "id: 12345\n"
}

How do I search for a range of Strings

2 Answers2