将字节数组转换为对象
本文关键字:对象 转换 数组 字节 字节数 | 更新日期: 2023-09-27 18:22:08
C#中有没有将纯字节数组转换为对象的方法?
例如,给定此类:
class Data
{
public int _int1;
public int _int2;
public short _short1;
public long _long1;
}
我想基本上能够做这样的事情:
var bytes = new byte[] { 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0 };
var obj = (Data)bytes;
您可以尝试编组:
将类的布局声明为Sequential(并注意您需要使用Pack = 1
):
[StructLayout(LayoutKind.Sequential, Pack = 1)]
class Data
{
public int _int1;
public int _int2;
public short _short1;
public long _long1;
}
将字节封送到Data类的新实例中:
var bytes = new byte[] { 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0 };
GCHandle gcHandle = GCHandle.Alloc(bytes, GCHandleType.Pinned);
var data = (Data)Marshal.PtrToStructure(gcHandle.AddrOfPinnedObject(), typeof(Data));
gcHandle.Free();
// Now data should contain the correct values.
Console.WriteLine(data._int1); // Prints 1
Console.WriteLine(data._int2); // Prints 2
Console.WriteLine(data._short1); // Prints 3
Console.WriteLine(data._long1); // Prints 4
为了方便起见,您可以在Data上编写一个静态方法来进行转换:
[StructLayout(LayoutKind.Sequential, Pack = 1)]
class Data
{
public int _int1;
public int _int2;
public short _short1;
public long _long1;
public static Data FromBytes(byte[] bytes)
{
GCHandle gcHandle = GCHandle.Alloc(bytes, GCHandleType.Pinned);
var data = (Data)Marshal.PtrToStructure(gcHandle.AddrOfPinnedObject(), typeof(Data));
gcHandle.Free();
return data;
}
}
...
var data = Data.FromBytes(new byte[] {1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0});
如果你真的想的话,你可以写一个显式运算符来从字节数组转换,以在你的OP中获得语法。我建议只使用Data.FromBytes()
,这将是一个更清晰的IMO.
不过,只是为了完整性:
[StructLayout(LayoutKind.Sequential, Pack = 1)]
class Data
{
public int _int1;
public int _int2;
public short _short1;
public long _long1;
public static explicit operator Data(byte[] bytes)
{
GCHandle gcHandle = GCHandle.Alloc(bytes, GCHandleType.Pinned);
var data = (Data)Marshal.PtrToStructure(gcHandle.AddrOfPinnedObject(), typeof(Data));
gcHandle.Free();
return data;
}
}
...
var data = (Data)new byte[] {1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 4, 0, 0, 0, 0, 0, 0, 0};
使用BitConverter.ToInt32/Int16/Int64
方法。您只需指定起始索引,如:
Data data = new Data();
data._int1 = BitConverter.ToInt32(bytes, 0);
data._int2 = BitConverter.ToInt32(bytes, 4);
data._short1 = BitConverter.ToInt16(bytes, 8);
data._long1 = BitConverter.ToInt64(bytes,10);
请记住:
BitConverter.ToInt32
数组中的字节顺序必须反映计算机系统体系结构;
这里有一种将字节数组转换为对象的方法。
var binaryFormatter = new BinaryFormatter();
using (var ms = new MemoryStream(bytes))
{
object obj = binaryFormatter.Deserialize(ms);
return (Data)obj;
}
没有什么能一次完成转换。
但您可以在BitConverter
:之上进行构建
var d = new Data();
var sI32 = sizeof(Int32);
d._int1 = BitConverter.ToInt32(bytes, 0);
d._int2 = BitConverter.ToInt32(bytes, sI32);
d._short1 = BitConverter.ToInt16(bytes, 2*sI32);
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