iOS开发 Plist 文件实现增、删、查、改

①有时候进行少量数据持久化存储时候，可使用属性列表 Plist 文件。

②如项目中要使用比较多的配置数据，可生成 Plist 后再转移到项目中

下面例子简单实现对于在沙盘下的 Plist 文件进行增删查改操作。

保存

更改

删除

import UIKit

class ViewController: UIViewController {
    
    @IBOutlet weak var userNumber: UITextField!
    @IBOutlet weak var userName: UITextField!
    @IBOutlet weak var userAge: UITextField!
    
    var filePath = "" //文件路径
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.createPlistFile()
    }
    
    //判断是否存在该plist文件，不存在则创建
    func createPlistFile() {
        //获取路径
        let path = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0]
        filePath = path.stringByAppendingString("/data666.plist")
        //###注意加横杆“/”，否则真机测试崩溃，因为无法写入####
        
        if !NSFileManager.defaultManager().fileExistsAtPath(filePath) {
            let rootDic = NSMutableDictionary()
            rootDic.writeToFile(filePath, atomically: true)
        }
    }
    
    //遍历数据
    func findPlistFileData() -> Bool {
        
        if let dicData = NSMutableDictionary(contentsOfFile: filePath) {
            for (k,_) in dicData {
                // 判断是否存在相同的学号
                if userNumber.text! == (k as! String) {
                    return true
                }
            }
        }
        return false
    }
    
    //保存数据
    func savePlistData() {
        
        let rootDic = NSMutableDictionary(contentsOfFile: filePath) //根
        let userDataDic = NSMutableDictionary()  //二级
        userDataDic.setObject(userAge.text!, forKey: "age")
        userDataDic.setObject(userName.text!, forKey: "name")
        rootDic!.setObject(userDataDic, forKey: userNumber.text!)
        rootDic!.writeToFile(filePath, atomically: true)
        print("保存成功")
    }
    
    //删除数据
    func deletePlistData() {

        let rootDic = NSMutableDictionary(contentsOfFile: filePath) //根
        rootDic!.removeObjectForKey(userNumber.text!) //二级
        rootDic!.writeToFile(filePath, atomically: true)
        print("删除成功")
    }
    
    // MARK: - Action
    // 保存按钮
    @IBAction func saveData(sender: UIButton) {
        //门卫 检查
        guard findPlistFileData() == false else {
            let alert = UIAlertController(title: "学号已存在", message: "是否要覆盖当前学号所有内容", preferredStyle: .Alert)
            alert.addAction(UIAlertAction(title: "是的", style: .Default, handler: { (action) -> Void in
                
                self.savePlistData() //保存数据
            }))
            alert.addAction(UIAlertAction(title: "否", style: .Cancel, handler: nil))
            self.presentViewController(alert, animated: true, completion: nil)
            return
        }
        
        self.savePlistData() //保存数据
        let alert = UIAlertController(title: "保存成功", message: "", preferredStyle: .Alert)
        alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
    }
    
    
    // 删除按钮
    @IBAction func deleteData(sender: UIButton) {
        //门卫 检查
        guard findPlistFileData() == true else {
            let alert = UIAlertController(title: "学号不存在", message: "请查看是否输入有误", preferredStyle: .Alert)
            alert.addAction(UIAlertAction(title: "确定", style: .Cancel, handler: nil))
            self.presentViewController(alert, animated: true, completion: nil)
            return
        }
        let alert = UIAlertController(title: "删除成功", message: "", preferredStyle: .Alert)
        alert.addAction(UIAlertAction(title: "确定", style: .Cancel, handler: nil))
        self.presentViewController(alert, animated: true, completion: nil)
        self.deletePlistData() //删除数据
    }
    
    // 查找按钮
    @IBAction func findData(sender: UIButton) {
        guard findPlistFileData() == true else {
            print("该学号不存在")
            return
        }
        if let dicData = NSMutableDictionary(contentsOfFile: filePath) {
            for (k,v) in dicData {
                if userNumber.text! == (k as! String) {
                    let dic2 = v as! NSDictionary
                    print("该学号已存在")
                    for (k1, v2) in dic2 {
                        print("\(k1): \(v2)")
                    }
                }
            }
        }
    }
}