如何将带有字符串数组的结构转换为 NSData，反之亦然 Swift答案

【问题标题】：How to Covert struct with an Array of string to NSData and vice versa Swift如何将带有字符串数组的结构转换为 NSData，反之亦然 Swift
【发布时间】：2015-10-12 09:33:29
【问题描述】：

我有这个结构：

struct MessageRandomWords {
        let message = MessageType.kMessageTypeRandomWords
        let randomWords : Array<Array<String>>
    }

我正在尝试通过这样做将此结构转换为 NSDate：

    var message = MessageRandomWords(randomWords: self.words)
    let data = NSData(bytes: &message, length: sizeof(MessageRandomWords))

但是当我尝试将其转换回原始结构时：

var messageRandomWords : MessageRandomWords?
                data.getBytes(&messageRandomWords, length: sizeof(MessageRandomWords))
                if let messageRandomWords = messageRandomWords {

}

我在 if let 语句中发现了 BAD_ACCESS 错误。问题出在哪里？

【问题讨论】：

标签： ios swift nsarray nsdata

【解决方案1】：

基于此答案： Swift structs to NSData and back 我写了这个解决方案：

struct MessageRandomWords {
    let message = MessageType.kMessageTypeRandomWords
    var data : NSData?
    var name: String

    struct ArchivedPacket {
        let message = MessageType.kMessageTypeRandomWords
        var dataLength : Int64
        var nameLength : Int64
    }

    func archive() -> NSData {
        var archivedPack = ArchivedPacket(dataLength: Int64(self.data!.length), nameLength: Int64(self.name.lengthOfBytesUsingEncoding(NSUTF8StringEncoding)))
        var metaData = NSData(bytes: &archivedPack, length: sizeof(ArchivedPacket))
        let archiveData = NSMutableData(data: metaData)
         archiveData.appendData(name.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)!)
        archiveData.appendData(data!)
        return archiveData
    }

    static func unarchive(data : NSData!) -> MessageRandomWords {
        var archivedPacket = ArchivedPacket(dataLength: 0, nameLength: 0)
        let archivedStructLength = sizeof(ArchivedPacket) //lenght of the struct

        //Get the data tha will form our archived Packet
        let archivedData = data.subdataWithRange(NSMakeRange(0, archivedStructLength))
        //save the data taht form the archivedPacket inside the archivedPacket
        archivedData.getBytes(&archivedPacket, length: archivedStructLength)
        //get the range of data that contains the name
        let nameRange = NSMakeRange(archivedStructLength, Int(archivedPacket.nameLength))
        //get the range of the data that contains the data
        let dataRange = NSMakeRange(archivedStructLength + Int(archivedPacket.nameLength), Int(archivedPacket.dataLength))
        //get the data that rappresent the name
        let nameData = data.subdataWithRange(nameRange)
        //Get the name frome the data
        let name = NSString(data: nameData, encoding: NSUTF8StringEncoding) as! String
        // Geth the data
        let theData = data.subdataWithRange(dataRange)

        //Create the struct
        let messageRndm = MessageRandomWords(data: theData, name: name)
        return messageRndm
    }

}

如果您创建如图所示的结构，您可以通过将字符串数组编码为 NSData 来发送它，然后在收到时对其进行解码。

您可以在 GitHub 上找到完整的工作示例

如果您有更好的解决方案，请留下一些反馈

【讨论】：