Finding a value in an array of arrays

Question

I have an array in the following format

var persons : [[String]] = []

let blah : [String] = [title, firstName, lastName, address1, town, postCode]

persons.append(blah)

Which gives output like :

[
   ["Mr", "Joe", "Bloggs", "999 Letsbe Avenue", "Townsville", "TS12 9UY"],
   ["Mr", "Peter", "Smith", "999 Underavest", "CityVille", "OP19 1IK"]
]

I want to do a search to find the first occurrence of "Smith" but I'm stumped on how to do it.

Any help please?

warning: Using arrays to model records like this is a bad idea, and will only lead you down a road of incorrect-index errors, type casting headaches and pain. It's better to use a struct or class to model your Person. At that point, the search becomes as easy and readable as people.first(where: { $0.lastName == "Smith }) — Alexander
– Alexander, Commented Nov 24, 2019 at 14:49

Shehata Gamal · Accepted Answer · 2019-11-24 14:16:17Z

1

You can try

if let index = persons.index(where:{ $0.contains("Smith")  }) { 
     print(index)  
}

Btw it's better to have

 struct Person {
    let fname,lname,address:String
 }

edited Nov 24, 2019 at 14:16

answered Nov 24, 2019 at 14:09

Shehata Gamal

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2 Comments

lonespeaker Over a year ago

Thank you, that's perfect! Do you know how I can get the row number of the matching entry? like if I search for "Smith" I get 2, and if I search for "Bloggs" I get 1 ?

lonespeaker Over a year ago

Thank you for your help, that's all been perfect.

Community · Accepted Answer · 2020-06-20 09:12:55Z

0

You can do something like this

let array = [
       ["Mr", "Joe", "Bloggs", "999 Letsbe Avenue", "Townsville", "TS12 9UY"],
       ["Mr", "Peter", "Smith", "999 Underavest", "CityVille", "OP19 1IK"]
    ]
    
    var index = array.flatMap { $0 }.firstIndex(of: "Smith")
    print("\(index!/5)")
     index = array.flatMap { $0 }.firstIndex(of: "Bloggs")
    print("\(index!/5)")

I have taken 5 to find the index as there are five entries in each array.

edited Jun 20, 2020 at 9:12

CommunityBot

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answered Nov 24, 2019 at 14:50

Mohammad Sadiq

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1 Comment

Alexander Over a year ago

You can use enumerated() to directly get the indices, rather than this flatMap + division trick (which will break the moment somebody adds/removes a field to the people's fields)

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