讀取文本文件並返回 swift 中的字典數組

Question

我正在嘗試讀取文本文件並返回 swift 中的字典數組

文本文件包含以下數據：

13582;Name 1;12345;5
13583;Name 2;23456;5
13585;Name 3;EX934;6
13598;Name 4;XE345_c;6
13600;Name 5;XF8765;6

 func machineNumberToName() -> [[String: String]] {
    var dic1 = [String: String]()
    var dic2 = [String: String]()
    var dic3 = [String: String]()
    var dic4 = [String: String]()
    // FileName for machines
    let fileName = "Machines.txt";
    if let path = Bundle.main.path(forResource: fileName, ofType: nil) {
        do {
            let contents = try! String(contentsOfFile: path)
            let lines = contents.split(separator: "\n")
            for line in lines {
                var entries = lines.split(separator: ";")
                dic1["machineNumber"] = entries[0]
                dic2["machineName"] = entries[1]
                dic3["machineXML"] = entries[2]
                dic4["wifi"] = entries[3]
                return [dic1, dic2, dic3, dic4]
            }
            
        } catch {
            print(error.localizedDescription)
        }
    } else {
        NSLog("file not found: \(fileName)")
        return []
    }
}

但是我得到了錯誤

Cannot assign value of type 'Array<String.SubSequence>.SubSequence' (aka 'ArraySlice<Substring>') to subscript of type 'String'

不知道我做錯了什么！

Answer 1

entries不是String的數組，它是ArraySlice<Substring>的數組，或者非正式的子字符串數組。

您可以使用String(entries[0])獲取要放入字典的字符串。

不過，您還有另一個問題； 你只會得到字典中的第一行，因為你return了循環。 即使你解決了這個問題，返回一個字典數組也很麻煩。 創建一個適當的結構並返回這些結構的數組

struct MachineDetails {
    let machineNumber: String
    let machineName: String
    let machineXML: String
    let machineWiFi: String
}

func getMachineDetails() -> [MachineDetails] {
    var details = [MachineDetails]()
    let fileName = "Machines.txt";
    if let path = Bundle.main.path(forResource: fileName, ofType: nil) {
        do {
            let contents = try String(contentsOfFile: path)
            let lines = contents.split(separator: "\n")
            for line in lines {
                let entries = line.split(separator: ";").map { String($0) }
                if entries.count == 4 {
                    let newMachine = MachineDetails(machineNumber:entries[0],
                         machineName:entries[1],
                         machineXML:entries[2],
                         machineWiFi:entries[3])
                     details.append(newMachine)
                } else {
                    print("Malformed line \(line)")
                }
            }   
        } catch {
            print(error.localizedDescription)
        }
    } else {
        NSLog("file not found: \(fileName)")
    }
    return details
}