iosswiftalgorithmnsarraystringbuilder

Swift Printing an Array in a table form String and also adding special characters


Lets assume i have this string

var stringCSV = "Beth,Charles,Danielle,Adam,Eric\n17945,10091,10088,3907,10132\n2,12,13,48,11";

And i converted it into a 2D Array

[["Beth", "Charles", "Danielle", "Adam", "Eric"], ["17945", "10091", "10088", "3907", "10132"], ["2", "12", "13", "48", "11"]]

Below is the code i used to convert the String into a 2D Array and sort it.

struct Person {
  let name: String
  let id: String
  let age: String
}

var csvFormatted = [[String]]()

stringCSV.enumerateLines { (line, _) in
  var res = line.split(separator: ",",omittingEmptySubsequences: false).map{ 
    String($0) 
  }
  for i in 0 ..< res.count {
    res[i] = res[i]
  }
  csvFormatted.append(res)
}

let properties = zip(csvFormatted[1],csvFormatted[2])
let namesAndProperties = zip(csvFormatted[0],properties)

let structArray = namesAndProperties.map { (name, properties) in
  return Person(name: name, id: properties.0, age: properties.1)
}

let sortedArray = structArray.sorted {
  return $0.name < $1.name
}

for i in sortedArray {
    print(i.name, i.id, i.age)
}

i get the below output

Adam 3907 48
Beth 17945 2
Charles 10091 12
Danielle 10088 13
Eric 10132 11

But I wont to understand and know how i can print the sorted array back to string, just like it was before i splitted it into an array and sorted it and including the special characters like "\n" and ",".

and achieve something the below

Adam,Beth,Charles,Danielle,Eric\n
3907,17945,10091,10088,10132\n
48,2,12,13,11

Solution

  • Use map for each property and join it to create a comma separated row. Then using the results in an array join again with a new line character.

    let csv = [array.map(\.name).joined(separator: ","),
               array.map(\.id).joined(separator: ","),
               array.map(\.age).joined(separator: ",")]
       .joined(separator: "\n")