Question

我是快速编程的新手，正在尝试从服务器获取JSON格式的用户数据，然后将其“粘贴”到结构中：

这是我的api：

app.get('/getUser/:username',(req,res)=>{
    let user = req.params;
    var sql = "SELECT * FROM  users WHERE username = ? ";
    mysqlConnection.query(sql,[user.username],
    function(err, rows){
        if(!err){    

       res.send(JSON.stringify({"userID" : rows}));
}
 else {
console.log(err)
         }
    });
});

这是JSON响应：

{
    userID =     (
                {
            email = test;
            id = 1;
            money = 200;
            password = test;
            username = test;
        }
    );
}

这是我的apiCall函数：

    class func  getUser(username :String)
    {          
            let url = "http://127.0.0.1:3000/getUser/"+username
            Alamofire.request(url).responseJSON(completionHandler : { (response) in
                switch response.result {
                case .success( _):
                    // I want to append the user struct by the user data collected from JSON
                    print(response.result.value!)

                case .failure(let error):
                    print (error)
                }

            })                   
        }

这是我的结构：

struct user {
    var id : String
    var username : String
    var password : String
    var email : String
    var money : String        
}

我试图在MainPageViewController中创建一个数组，然后追加它，但是我不知道如何：

class MainPageViewController: UIViewController {
    var currentUser : String?
    var userData = [user]()
    override func viewDidLoad() {
        API.getUser(username: currentUser!)
        print(currentUser!)

        super.viewDidLoad()
     //   API.getUserID(username: currentUser!)
        // Do any additional setup after loading the view.
    }

Answer 1

您可以尝试

struct Root: Codable {
    let userID: [User]
}

struct User: Codable {
    let email: String
    let id, money: Int
    let password, username: String
}

do {
    let res = try JSONDecoder().decode(Root.self,from:data)
    users = res.userID
 }
 catch {
    print(error)
 }

并将Alamofire从responseJSON更改为responseData

Alamofire.request(url).responseData(completionHandler : { (response) in
    switch response.result {
    case .success( let data):
        // I want to append the user struct by the user data collected from JSON
        print(response.result.value!)
        do {
            let res = try JSONDecoder().decode(Root.self,from:data)
            userData = res.userID
        }
        catch {
            print(error)
        }

    case .failure(let error):
        print (error)
    }

})

Answer 2

最好的方法是使用Codeable：

let data: YourJSONData

struct User: Codable {
    var id: String
    var username: String
    var password: String
    var email: String
    var money: String
}

let user = try? JSONDecoder().decode(User.self, from: data)

编辑

要回答您的进一步问题，请像这样使用它：

static func getUserByUsername(_ username: String) {
    let url = "http://127.0.0.1:3000/getUser/" + username

    Alamofire.request(url).responseData(completionHandler : { (response) in
        switch response.result {
        case .success( let data):

            do {
                let user = try JSONDecoder().decode(Base.self, from: data)
            }
            catch {print(error)}

        case .failure(let error):
            print (error)
        }

    })
}

struct Base: Codable {
    let userID: [User]
}

struct User: Codable {
    var id: String
    var username: String
    var password: String
    var email: String
    var money: String
}

快速将JSON响应转换为结构

2 个答案: