轉換單個字符串座標成CLLocationCoordinate2D陣列和使用該陣列在MapView生成多邊形

Question

我收到此JSON：

JSON: { 
    "status_code" : 200, 
    "status" : "ok", 
    "data" : [ 
    { 
     "zona" : "Narvarte", 
     "hora" : "", 
     "id_zona" : 1423, 
     "proxdia" : "Lunes 20 de Febrero, 2017", 
     "coor" : "(19.452187074041884, -99.1457748413086),(19.443769985032485, -99.14852142333984),(19.443446242121073, -99.13787841796875),(19.450244707639662, -99.13822174072266)", 
     "dias" : "Lunes" 
    }, ...] 

哪我存儲在這個結構：

struct RutaItem { 
var idZona: Int 
var dias: String 
var proxDia: String 
var hora: String 
var coor: String 
var zona: String 
} 

然後創建的[RutaItem]陣列，其中我存儲的結構

var rutaItemArray = [RutaItem]() 

一旦數據已存儲的內部rutaItemArray的結構是這樣的：

[pixan.RutaItem(idZona: 1423, dias: "Lunes", proxDia: "Lunes 20 de Febrero, 2017", hora: "", coor: "(19.452187074041884, -99.1457748413086),(19.443769985032485, -99.14852142333984),(19.443446242121073, -99.13787841796875),(19.450244707639662, -99.13822174072266)", zona: "Narvarte")...] 

我現在需要做的是使用String的rutaItemArray.coor每個索引內部產生MKPolygonObject，所以首先我需要的長字符串轉換成4 CLLocationCoordinate2D對象並將這4個座標對象放入數組中，然後使用數組索引爲不同區域生成多邊形。

有人可以幫我解決這個問題嗎？

Answer 1

您可以使用正則表達式模式匹配。 解釋內聯：

let coordString = "(19.452187074041884, -99.1457748413086), (19.443769985032485, -99.14852142333984),(19.443446242121073, -99.13787841796875),(19.450244707639662, -99.13822174072266)" 

// Regular expression pattern for "(... , ...)" 
let pattern = "\\((.+?),(.+?)\\)" 
let regex = try! NSRegularExpression(pattern: pattern) 

// We need an NSString, compare http://stackoverflow.com/a/27880748/1187415 
let nsString = coordString as NSString 

// Enumerate all matches and create an array: 
let coords = regex.matches(in: coordString, range: NSRange(location: 0, length: nsString.length)) 
    .flatMap { match -> CLLocationCoordinate2D? in 
     // This closure is called for each match. 

     // Extract x and y coordinate from match, remove leading and trailing whitespace: 
     let xString = nsString.substring(with: match.rangeAt(1)).trimmingCharacters(in: .whitespaces) 
     let yString = nsString.substring(with: match.rangeAt(2)).trimmingCharacters(in: .whitespaces) 

     // Convert to floating point numbers, skip invalid entries: 
     guard let x = Double(xString), let y = Double(yString) else { return nil } 

     // Return CLLocationCoordinate2D: 
     return CLLocationCoordinate2D(latitude: x, longitude: y) 
} 

Answer 2

這是我想出的。你可以調整它以適應你的結構。

import Foundation 

let input = "(19.452187074041884, -99.1457748413086),(19.443769985032485, -99.14852142333984),(19.443446242121073, -99.13787841796875),(19.450244707639662, -99.13822174072266)" 

// Remove leading `(` and trailing `)` 
let trimmedInput = String(input.characters.dropLast().dropFirst()) 

let coordStrings = trimmedInput.components(separatedBy: "),(") 

let coords: [CLLocationCoordinate2D] = coordStrings.map{ coordsString in 
    let coords = coordsString.components(separatedBy: ", ") 
    precondition(coords.count == 2, "There should be exactly 2 coords.") 
    guard let lat = Double(coords[0]), 
      let long = Double(coords[1]) else { 
     fatalError("One of the coords isn't a valid Double: \(coords)") 
    } 

    return CLLocationCoordinate2D(latitude: lat, longitude: long) 
} 

print(coords)