初衷

眾所周知鲸湃，在OC時(shí)代浓镜，MJ大神使用一句宏定義MJCodingImplementation就搞定了歸解檔中繁瑣的編碼與解碼工作锭魔。而在Swift中，沒有Runtime大法咬荷，在日常編碼過程中遇到需要?dú)w檔的模型冠句，只要寫編碼和解碼方法，就會(huì)寫到吐血幸乒。于是我找到了Swift中的Reflect特性來幫助我們簡化這部分的工作懦底。

效果

在使用JXAutoEncoder這個(gè)工具類之前，要完成一個(gè)類的歸檔工作需要編寫類似以下的代碼

class ArchiverModel: NSObject, NSCoding {

    var bool = true
    var int = 1
    var double = M_PI
    var string = ""
    var array = ["123", "456"]
    var dictionary = ["abc": "cba"]
    var data = "hello world".data(using: String.Encoding.utf8)
    var date = Date()


    /// 歸檔到文件
    func archiveToFile() {
        var modelFile = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory,
                                                            FileManager.SearchPathDomainMask.userDomainMask,
                                                            true)[0]
        modelFile += "/model.data"
        NSKeyedArchiver.archiveRootObject(self, toFile: modelFile)
    }

    /// 從文件中解檔
    ///
    /// - Returns: 解檔后的Model
    class func decodedFromFile() throws -> ArchiverModel {
        var modelFile = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory,
                                                            FileManager.SearchPathDomainMask.userDomainMask,
                                                            true)[0]
        modelFile += "/model.data"

        if FileManager.default.fileExists(atPath: modelFile) {
            if let model = NSKeyedUnarchiver.unarchiveObject(withFile: modelFile) as? ArchiverModel {
                return model
            }else{
                throw NSError(domain: "Unarchive fail", code: 100, userInfo: nil)
            }
        }else{
            throw NSError(domain: "File doesn't exists", code: 101, userInfo: nil)
        }
    }

    required init?(coder aDecoder: NSCoder) {
        super.init()
        if let boolValue = aDecoder.decodeObject(forKey: "bool") as? Bool {
            bool = boolValue
        }
        if let intValue = aDecoder.decodeObject(forKey: "int") as? Int {
            int = intValue
        }
        if let doubleValue = aDecoder.decodeObject(forKey: "double") as? Double {
            double = doubleValue
        }
        if let stringValue = aDecoder.decodeObject(forKey: "string") as? String {
            string = stringValue
        }
        if let arrayValue = aDecoder.decodeObject(forKey: "array") as? [String] {
            array = arrayValue
        }
        if let dictionaryValue = aDecoder.decodeObject(forKey: "dictionary") as? [String: String] {
            dictionary = dictionaryValue
        }
        if let dataValue = aDecoder.decodeObject(forKey: "data") as? Data {
            data = dataValue
        }
        if let dateValue = aDecoder.decodeObject(forKey: "date") as? Date {
            date = dateValue
        }
    }

    func encode(with aCoder: NSCoder) {
        aCoder.encode(bool, forKey: "bool")
        aCoder.encode(int, forKey: "int")
        aCoder.encode(double, forKey: "double")
        aCoder.encode(string, forKey: "string")
        aCoder.encode(array, forKey: "array")
        aCoder.encode(dictionary, forKey: "dictionary")
        aCoder.encode(data, forKey: "data")
        aCoder.encode(date, forKey: "date")
    }
}

密密麻麻的aCoder.encode看得我密集恐懼癥都犯了逝变，更別說這個(gè)類如果要添加新的屬性會(huì)怎樣了，并且當(dāng)屬性變多奋构，encode和decode就很容易漏寫壳影，造成應(yīng)用崩潰。使用工具類之后弥臼，這種情況就可以完全避免了宴咧，如下所示：

import JXAutoEncoder

class ArchiverModel: JXAutoEncoder {

    var bool = true
    var int = 1
    var double = M_PI
    var string = ""
    var array = ["123", "456"]
    var dictionary = ["abc": "cba"]
    var data = "hello world".data(using: String.Encoding.utf8)
    var date = Date()


    /// 歸檔到文件
    func archiveToFile() {
        var modelFile = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory,
                                                            FileManager.SearchPathDomainMask.userDomainMask,
                                                            true)[0]
        modelFile += "/model.data"
        NSKeyedArchiver.archiveRootObject(self, toFile: modelFile)
    }

    /// 從文件中解檔
    ///
    /// - Returns: 解檔后的Model
    class func decodedFromFile() throws -> ArchiverModel {
        var modelFile = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory,
                                                            FileManager.SearchPathDomainMask.userDomainMask,
                                                            true)[0]
        modelFile += "/model.data"

        if FileManager.default.fileExists(atPath: modelFile) {
            if let model = NSKeyedUnarchiver.unarchiveObject(withFile: modelFile) as? ArchiverModel {
                return model
            }else{
                throw NSError(domain: "Unarchive fail", code: 100, userInfo: nil)
            }
        }else{
            throw NSError(domain: "File doesn't exists", code: 101, userInfo: nil)
        }
    }
}

簡潔明了，干凈透徹径缅，若要增加屬性掺栅，則直接var...就好了，是不是方便了許多纳猪。

部署

JXAutoEncoder這個(gè)工具類支持pod導(dǎo)入氧卧，導(dǎo)入方式pod 'JXAutoEncoder' ,具體可查閱項(xiàng)目主頁。使用中若發(fā)現(xiàn)Bug氏堤，請(qǐng)?zhí)醝ssue沙绝，使用順手請(qǐng)star，謝謝??鼠锈！