如何在 swift 中从 GET url 创建 struct 和 init 值

Question

我的 JSON：

   {
  "id": "70",
  "bname": "Municipal Corporation - Water",
  "bcategoryname": "Water",
  "bcustomerparms": "[{\"paramName\":\"Consumer Number\",\"dataType\":\"NUMERIC\",\"optional\":\"false\",\"minLength\":\"1\",\"maxLength\":\"10\" .      },
           {\"paramName\":\"Mobile Number\",\"dataType\":\"NUMERIC\",\"optional\":\"false\",\"minLength\":\"10\",\"maxLength\":\"10\"},
           {\"paramName\":\"Email . Id\",\"dataType\":\"ALPHANUMERIC\",\"optional\":\"false\",\"minLength\":\"5\",\"maxLength\":\"100\"}]",
 }
  {    
 "id": "68",
 "bname": "Municipal Corporation - 12",
 "bcategoryname": "Water",
 "bcustomerparms": "[{\"paramName\":\"K No\",\"dataType\":\"ALPHANUMERIC\",\"optional\":\"false\",\"minLength\":\"7\",\"maxLength\":\"20\"}]",
 } 

我无法从 get api 创建结构，我需要根据 bcategoryname 的 bname 和它的 paramNamew，我需要在 table 中显示 bname，如果我选择我需要它的所有 paramNames。

代码如下：

struct JsonDataBiller{
var bname: String?
var bcategoryname: String?
var bcustomerparms: [cDetails]

init(bname: String, bcategoryname: String, bcustomerparms: [cDetails]){

    self.bname = bname
    self.bcategoryname = bcategoryname
    self.bcustomerparms = bcustomerparms
}
}

struct cDetails{
var paramName: String?
var minLength: String?
var maxLength: String?

init(paramName: String, minLength: String, maxLength: String)
{
    self.paramName = paramName
    self.minLength = minLength
    self.maxLength = maxLength
}
}

代码：

class AllMakePaymentViewController: UIViewController {

@IBOutlet weak var tableView: UITableView!

var jsonData = [JsonDataBiller]()

var minLength: String?
var maxLength: String?
var bName: String?
var category: Category?
var categoryName: String?
var paramName: String?

var ParamArray = [String]()

var labelText: String?
override func viewDidLoad() {
    super.viewDidLoad()

    allPaymentService()
}

func allPaymentService(){

    let urlStr = "https://dev.anyemi.com/webservices/anyemi/api.php?rquest=billermdm"
    let url = URL(string: urlStr)
    URLSession.shared.dataTask(with: url!, completionHandler: {(data, response, error) in
        guard let respData = data else {
            return
        }
        guard error == nil else {
            print("error")
            return
        }
        do{
            let jsonObj = try JSONSerialization.jsonObject(with: respData, options: .allowFragments) as! [String: Any]
            //print("the all make payment json is \(jsonObj)")
            let billerdetailsArray = jsonObj["billerdetails"] as! [[String: Any]]

            for billerdetail in billerdetailsArray {

                self.categoryName = billerdetail["bcategoryname"] as? String

                let customrParams = billerdetail["bcustomerparms"] as! String
                let res = try JSONSerialization.jsonObject(with:Data(customrParams.utf8)) as! [[String: Any]]

                for item in res {

                    self.paramName = item["paramName"] as? String

                    self.minLength = item["minLength"] as? String
                    self.maxLength = item["maxLength"] as? String
                                            if self.categoryName == "Water"{
                        let bName = billerdetail["bname"] as? String
                        self.jsonData.append(JsonDataBiller(bname: bName ?? "", bcategoryname: self.categoryName ?? "", bcustomerparms: [paramName: paramName, minLength: minLength, maxLength: maxLength]))

                    }
                    if self.categoryName == "Electricity"{
                        let bName = billerdetail["bname"] as? String
                        self.jsonData.append(JsonDataBiller(bname: bName ?? "", bcategoryname: self.categoryName ?? "", bcustomerparms: [paramName: paramName, minLength: minLength, maxLength: maxLength]))
                    }
                }
            }
            DispatchQueue.main.async {
                self.tableView.reloadData()
            }
        }catch {
            print("catch error")
        } }).resume()
}
}

错误：

上下文类型 '[cDetails]' 不能与字典文字一起使用

这里我需要根据其bcategoryname添加bnam和根据bname添加paramName

请在上面的代码中帮助我，我无法解决这个问题，我卡住了很长时间。

Answer 1

如果您正在努力创建结构，您可以尝试使用这个网站，它会自动完成：

https://app.quicktype.io/

*不过，我还是建议先理解这个概念，然后再使用这样的助手

在您的情况下，您的 JSON 文件存在问题。

您的 JSON 的第一部分应该如下所示：

{ “身份证”：70， “bname”：“市政公司 - 水”， "bcategoryname": "水", “bcustomerparms”：[ { "paramName": "消费者编号", “数据类型”：“数字”， “可选”：假， “最小长度”：1， “最大长度”：10} ] }

// MARK: - DataStructure
struct DataStructure: Codable {
    let id: Int
    let bname, bcategoryname: String
    let bcustomerparms: [Bcustomerparm]
}

// MARK: - Bcustomerparm

struct Bcustomerparm: Codable {
    let paramName, dataType: String
    let bcustomerparmOptional: Bool
    let minLength, maxLength: Int

enum CodingKeys: String, CodingKey {
    case paramName, dataType
    case bcustomerparmOptional = "optional"
    case minLength, maxLength
}

}

Answer 2

你越来越近了……

关键步骤问题是您正在遍历“客户参数”并为每个参数添加一个新客户对象，而不是添加 一个 包含的客户对象参数数组。

看看这个 - 它应该在没有任何编辑的情况下运行。解析数据后，它将打印 Water 客户列表及其相关参数。

调试输出应如下所示：

Water count: 18
Electricity count: 71

Name: Bhopal Municipal Corporation - Water
Cat:  Water
Param: Connection ID / minLength: 8 / maxLength: 8

Name: Bangalore Water Supply and Sewerage Board
Cat:  Water
Param: RR Number / minLength: 8 / maxLength: 8

Name: Delhi Jal Board
Cat:  Water
Param: K No / minLength: 10 / maxLength: 10

...

Name: Municipal Corporation Jalandhar
Cat:  Water
Param: Account No / minLength: 1 / maxLength: 1
Param: Consumer Mobile No / minLength: 10 / maxLength: 10
Param: Consumer Email ID / minLength: 5 / maxLength: 5
Param: UID / minLength: 1 / maxLength: 1

Name: Municipal Corporation Ludhiana - Water
Cat:  Water
Param: Consumer Number / minLength: 1 / maxLength: 1
Param: Mobile Number / minLength: 10 / maxLength: 10
Param: Email Id / minLength: 5 / maxLength: 5

Name: New Delhi Municipal Council (NDMC) - Water
Cat:  Water
Param: Consumer Number / minLength: 7 / maxLength: 7

...

这里是来源：

//    
import UIKit

struct JsonDataBiller{
    var bname: String?
    var bcategoryname: String?
    var bcustomerparms: [cDetails]

    init(bname: String, bcategoryname: String, bcustomerparms: [cDetails]){

        self.bname = bname
        self.bcategoryname = bcategoryname
        self.bcustomerparms = bcustomerparms
    }
}

struct cDetails{
    var paramName: String?
    var minLength: String?
    var maxLength: String?

    init(paramName: String, minLength: String, maxLength: String)
    {
        self.paramName = paramName
        self.minLength = minLength
        self.maxLength = maxLength
    }
}

class AllMakePaymentViewController: UIViewController {

    // arrays of JsonDataBiller objects for each category
    var jsonWaterData = [JsonDataBiller]()
    var jsonElectricityData = [JsonDataBiller]()
    // ...

    override func viewDidLoad() {
        super.viewDidLoad()

        allPaymentService()
    }

    func allPaymentService(){

        let urlStr = "https://dev.anyemi.com/webservices/anyemi/api.php?rquest=billermdm"
        let url = URL(string: urlStr)
        URLSession.shared.dataTask(with: url!, completionHandler: {(data, response, error) in

            guard let respData = data else {
                return
            }
            guard error == nil else {
                print("error")
                return
            }
            do{
                let jsonObj = try JSONSerialization.jsonObject(with: respData, options: .allowFragments) as! [String: Any]
                //print("the all make payment json is \(jsonObj)")
                let billerdetailsArray = jsonObj["billerdetails"] as! [[String: Any]]

                for billerdetail in billerdetailsArray {

                    // make these local vars --- no need for the confusing self. properties
                    let localBName = billerdetail["bname"] as? String ?? ""
                    let localCName = billerdetail["bcategoryname"] as? String  ?? ""

                    let customrParams = billerdetail["bcustomerparms"] as! String
                    let res = try JSONSerialization.jsonObject(with:Data(customrParams.utf8)) as! [[String: Any]]

                    // create new array of cDetails objects
                    var aParams = [cDetails]()

                    // for each param item
                    for item in res {

                        if let pn = item["paramName"] as? String,
                            let minL = item["minLength"] as? String,
                            let maxL = item["maxLength"] as? String {

                            // create new cDetails object
                            let cd = cDetails(paramName: pn, minLength: minL, maxLength: maxL)

                            // append it to the aParams array
                            aParams.append(cd)

                        }

                    }

                    // create new JsonDataBiller object with
                    //      bname
                    //      bcategoryname
                    //      array of bcustomerparms
                    let jdBiller = JsonDataBiller(bname: localBName,
                                                  bcategoryname: localCName,
                                                  bcustomerparms: aParams)

                    // append the JsonDataBiller object to the appropriate category array
                    if localCName == "Water" {
                        self.jsonWaterData.append(jdBiller)
                    }
                    if localCName == "Electricity" {
                        self.jsonElectricityData.append(jdBiller)
                    }
                    // if localCName == ...

                }

                // finished parsing the data into arrays of jdBiller objects
                print("Water count: \(self.jsonWaterData.count)")
                print("Electricity count: \(self.jsonElectricityData.count)")
                print()

                // for quick debugging...
                self.jsonWaterData.forEach {
                    obj in
                    print("Name: \(obj.bname ?? "")")
                    print("Cat:  \(obj.bcategoryname ?? "")")
                    obj.bcustomerparms.forEach {
                        param in
                        print("Param: \(param.paramName ?? "") / minLength: \(param.minLength ?? "") / maxLength: \(param.minLength ?? "")")
                    }
                    print()
                }

//              DispatchQueue.main.async {
//                  self.tableView.reloadData()
//              }

            }catch {
                print("catch error")
            } }).resume()
    }
}