dispatch_data_t转换为nsstring

Question

我试图在swift中实现PeerTalk框架。 获取这类当MAC是给我的数据：

public class PTData : NSObject { 
public var dispatchData: dispatch_data_t! { get } 
public var data: UnsafeMutablePointer<Void> { get } 
public var length: Int { get } 

}

人们会认为，一个简单的转换和nil检查将做到：PTData类型的

if payload != nil { 
     let databis = NSData(bytesNoCopy: payload.data, length: payload.length, freeWhenDone: false) 
     let data = NSData(contentsOfDispatchData: payload.dispatchData) 
     let str = NSString(data: data, encoding: NSUTF8StringEncoding) 
     let strbis = NSString(data: databis, encoding: NSUTF8StringEncoding) 
     print("data is receive") 
     print(str) 
     print(strbis) 
    } 

有效载荷的存在！如前所述。 无我试过的方法，努力让我的字符串返回，我得到这个：

数据接收

可选（）

任何想法？

Answer 1

let strbis = NSString(data: databis, encoding: NSUTF8StringEncoding) 

返回一个可选类型的NSString?

所以，你应该写类似：

if payload != nil { 
    let databis = NSData(bytesNoCopy: payload.data, length: payload.length, freeWhenDone: false) 
    let data = NSData(contentsOfDispatchData: payload.dispatchData) 
    let str = NSString(data: data, encoding: NSUTF8StringEncoding) 
    let strbis = NSString(data: databis, encoding: NSUTF8StringEncoding) 
    print("data is receive") 
    if str != nil { 
     print(str!) 
    } 
    if strbis != nil { 
     print(strbis!) 
    } 
}