如何在通用 iOS 设备而不是模拟器上使用 FMDB?

本文介绍了如何在通用 iOS 设备而不是模拟器上使用 FMDB?的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我使用 Swift3 和 Xcode8 创建了一个应用程序，并使用 FMDB 作为我的数据库，当它在模拟器上运行时，它可以从 data.db 获取数据，但是当它在模拟器上运行时通用设备(这是我的手机)，tableView 中没有数据，也无法插入记录.我在我的项目中添加了 data.db，但是当我在模拟器上更改记录时，data.db 中的记录没有改变，但是我打印了路径，它指向模拟器文件夹，该文件夹中的数据库会随着模拟器中的修改而改变，并且该文件夹的路径几乎每次都会改变.我很困惑，是不是因为我实际上没有连接到我的数据库?

I've created an app using Swift3 and Xcode8, and using FMDB as my database, when it runs on the simulator it can get the data from data.db,but when it runs on the generic device (which is my phone), there's no data in the tableView, also could't insert records. I added data.db into my project, but when I changed records on simulator, records in data.db didn't change, but I printed the path, it pointed to simulator folder, database in that folder will changed along the modify in simulator and that folder's path changes almost every time. I'm so confused, is that because I didn't connected to my database in fact?

这里是 Utility.Swift ，它包含常见且经常重用的函数

Here's the Utility.Swift which holds common and often reused function

import UIKit

class Utility: NSObject {

class func getPath(_ fileName: String) -> String {
    let documentsURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
    let fileURL = documentsURL.appendingPathComponent(fileName)
    print(fileURL.path)
    return fileURL.path
    }

class func copyFile(_ fileName: NSString){

    let dbPath: String = getPath(fileName as String)
    let fileManager = FileManager.default

    if !fileManager.fileExists(atPath: dbPath) {
        let documentsURL = Bundle.main.resourceURL
        let fromPath = documentsURL!.appendingPathComponent(fileName as String)

        var error : NSError?
        do {
            try fileManager.copyItem(atPath: fromPath.path, toPath: dbPath)
        }
        catch let error1 as NSError {
            error = error1
        }
        let alert: UIAlertView = UIAlertView()
        if (error != nil) {
            alert.title = "Error Occured"
            alert.message = error?.localizedDescription
        }
        else {
            alert.title = "Successfully Copy"
            alert.message = "Your database copy successfully"
        }
        alert.delegate = nil
        alert.addButton(withTitle: "Ok")
        alert.show()
        }
    }

class func invokeAlertMethod(_ strTitle: NSString, strBody: NSString, delegate: AnyObject?) {
    let alert: UIAlertView = UIAlertView()
    alert.message = strBody as String
    alert.title = strTitle as String
    alert.delegate = delegate
    alert.addButton(withTitle: "Ok")
    alert.show()
    }
}

和 StudentDataBase.swift 包含查询语言

import UIKit
let sharedInstance = StudentDataBase()

class StudentDataBase : NSObject {

var database: FMDatabase? = nil

class func getInstance() -> StudentDataBase{

    if((sharedInstance.database) == nil)
    {
        sharedInstance.database = FMDatabase(path: Utility.getPath("data.db"))
    }
    return sharedInstance
}


func addStuData(_ student: Student) -> Bool{

    sharedInstance.database!.open()

    let isInserted = sharedInstance.database!.executeUpdate("INSERT INTO [Student info] (StudentID, FirstName, LastName, PhoneNumber) VALUES (?, ?, ?, ?)", withArgumentsIn: [student.studentID, student.fstName, student.lstName, student.phoneNum])

    sharedInstance.database!.close()
    return isInserted
}


func updateStuData(_ student: Student) -> Bool {

    sharedInstance.database!.open()

    let isUpdated = sharedInstance.database!.executeUpdate("UPDATE [Student info] SET FirstName=?, LastName=?, PhoneNumber=? WHERE StudentID=?", withArgumentsIn: [student.fstName, student.lstName, student.phoneNum, student.studentID])
    print(student)
    print(isUpdated)
    sharedInstance.database!.close()
    return isUpdated
}


func deleteStuData(_ student: Student) -> Bool {

    sharedInstance.database!.open()

    let isDeleted = sharedInstance.database!.executeUpdate("DELETE FROM [Student info] WHERE StudentID=?", withArgumentsIn: [student.studentID])

    sharedInstance.database!.close()
    return isDeleted
}

func getAllStuData() -> [Student] {

    sharedInstance.database!.open()

    let resultSet: FMResultSet! = sharedInstance.database!.executeQuery("SELECT * FROM [Student info]", withArgumentsIn: nil)
    var marrStudentInfo : [Student] = []
    if (resultSet != nil) {
        while resultSet.next() {
            let student : Student = Student()
            student.studentID = resultSet.string(forColumn: "StudentID")
            student.fstName = resultSet.string(forColumn: "FirstName")
            student.lstName = resultSet.string(forColumn: "LastName")
            student.phoneNum = resultSet.string(forColumn: "PhoneNumber")
            marrStudentInfo.append(student)
        }
    }
    sharedInstance.database!.close()
    return marrStudentInfo
}
}

也在 AppDelegate.swift 中，我写了:

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    // Override point for customization after application launch.
    Utility.copyFile("data.db")
    return true
}

我是 Swift 和 FMDB 的新手，请解释一下，我会尽力而为.非常感谢！！！！

I'm new to Swift and FMDB, please explain and I'll try my best.Thank you very much!!!!

下载完手机里的内容后，数据库是空白的.在我扔掉错误后，它显示

After I downloaded the contents in my phone and the database is blank. And after I throwaway the error, it shows

Inserted failed:Optional("no such table: Student info")

设备而不是模拟器上使用

如何在通用 iOS 设备而不是模拟器上使用 FMDB?

问题描述

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