使用Swift我想将字节从uint8_t数组转换为整数。
“C”示例:
char bytes[2] = {0x01,0x02}; NSData *data = [NSData dataWithBytes:bytes length:2]; NSLog(@"data: %@",data); // data: <0102> uint16_t value2 = *(uint16_t *)data.bytes; NSLog(@"value2: %i",value2); // value2: 513
Swift尝试:
let bytes:[UInt8] = [0x01,0x02] println("bytes: \(bytes)") // bytes: [1,2] let data = NSData(bytes: bytes,length: 2) println("data: \(data)") // data: <0102> let integer1 = *data.bytes // This fails let integer2 = *data.bytes as UInt16 // This fails let dataBytePointer = UnsafePointer<UInt16>(data.bytes) let integer3 = dataBytePointer as UInt16 // This fails let integer4 = *dataBytePointer as UInt16 // This fails let integer5 = *dataBytePointer // This fails
从Swift中的UInt8数组创建UInt16值的正确语法或代码是什么?
我对NSData版本感兴趣,并且正在寻找一个不使用临时数组的解决方案。
如果你想通过NSData去,那么它将像这样工作:
原文链接:https://www.f2er.com/swift/320735.htmllet bytes:[UInt8] = [0x01,length: 2) print("data: \(data)") // data: <0102> var u16 : UInt16 = 0 ; data.getBytes(&u16) // Or: let u16 = UnsafePointer<UInt16>(data.bytes).memory println("u16: \(u16)") // u16: 513
或者:
let bytes:[UInt8] = [0x01,0x02] let u16 = UnsafePointer<UInt16>(bytes).memory print("u16: \(u16)") // u16: 513
两种变体都假定字节是主机字节顺序。
更新Swift 3(Xcode 8):
let bytes: [UInt8] = [0x01,0x02] let u16 = UnsafePointer(bytes).withMemoryRebound(to: UInt16.self,capacity: 1) { $0.pointee } print("u16: \(u16)") // u16: 513