4
我試圖編寫一個高級網絡庫（主要是爲了好玩），以便用戶可以通過派生類輕鬆定義它們的數據包。這種解析消息的方式非常簡單。用戶數據包應只包含基本值types。注入泛型getter和setter以獲得比反射更好的性能
爲了做到這一點，我需要訪問每個用戶定義數據包的每個字段。這個問題很容易用反射來完成，但由於反射速度很慢，所以我不能使用它。爲了做到這一點，我做了一個類，在運行時爲每個用戶定義的數據包字段注入getter和setter（在StackOverflow的某處找到它）。獲得者是Func<UserDefinedPacket, fieldType>，並且制定者是Action<UserDefinedPAcket, setValue>。
這裏的問題是：因爲用戶分組在另一組件I所定義不可能知道的吸氣劑或設置器在編譯時的類型。我可以用於getter和setter的派生類最多的是Delegate。這意味着我只能使用DynamicInvoke，所以我再次進行反射......但是因爲我知道這些方法實際上是Funcs和Actions，但實際上並不能轉換它們，所以我可以使用動態類型並調用Invoke。動態類型將性能提高了約5倍，但與正常字段訪問相比，設置和獲取值的速度仍然較慢（約快100倍），導致此庫無法使用。
最終我希望能夠將用戶定義的類轉換爲字節數組。我也不想序列化這個類，因爲序列化包含了一些垃圾數據，我真的不想通過網絡發送，而且序列化看起來很慢。
這裏是問題：我真的可以讓GetVaue和SetValue方法更快嗎？我嘗試將代理投射到所需的功能/操作（將圖庫中的自定義數據包類移動，所以這不太好），並且安裝程序花費了大約50ms而不是300ms。我希望能夠獲得通用數據包的性能。
namespace MirrorNet
{
// Base class for packets
// This will be derived by users and should only contain basic type fields
public class UserPacket
{
}
public class MirrorNetManager
{
private static MirrorNetManager instance = new MirrorNetManager();
public static MirrorNetManager Instance
{
get { return instance; }
}
// Dictionary: packetType -> field -> getter | setter
private class PropertyDictionary : Dictionary<Type, Dictionary<FieldInfo, Delegate>>
{
}
private Dictionary<int, PacketConstructor> m_packetConstructors = new Dictionary<int, PacketConstructor>();
private PropertyDictionary m_packetFieldGetters = new PropertyDictionary();
private PropertyDictionary m_packetFieldSetters = new PropertyDictionary();
public void SetValue(UserPacket packet, FieldInfo field, object value)
{
var setDelegate = m_packetFieldSetters[packet.GetType()][field];
dynamic setAction = setDelegate; //Convert.ChangeType(setDelegate, setDelegate.GetType());
dynamic setObject = packet; //Convert.ChangeType(packet, packet.GetType());
dynamic setValue = value; //Convert.ChangeType(value, value.GetType());
setAction.Invoke(setObject, setValue);
//setDelegate.DynamicInvoke(packet, value);
}
public object GetValue(UserPacket packet, FieldInfo field)
{
var getDelegate = m_packetFieldGetters[packet.GetType()][field];
dynamic getFunction = getDelegate; //Convert.ChangeType(getDelegate, getDelegate.GetType());
dynamic getObject = packet; //Convert.ChangeType(packet, packet.GetType());
return getFunction.Invoke(getObject);
//return getDelegate.DynamicInvoke(packet);
}
public void InitializePackets(Assembly packetsAssembly)
{
var typesArray = packetsAssembly.GetTypes();
foreach (Type type in typesArray)
{
if (type.BaseType == typeof(UserPacket))
{
InsertPacketConstructor(type);
InsertSettersAndGetters(type);
}
}
}
private void InsertPacketConstructor(Type packetType)
{
foreach (var member in packetType.GetFields())
{
Console.WriteLine(member);
// TODO: Implement
}
}
private void InsertSettersAndGetters(Type type)
{
Dictionary<FieldInfo, Delegate> getters = new Dictionary<FieldInfo, Delegate>();
Dictionary<FieldInfo, Delegate> setters = new Dictionary<FieldInfo, Delegate>();
foreach (FieldInfo field in type.GetFields())
{
Delegate getDelegate = CreateGetter(type, field.FieldType, field);
Delegate setDelegate = CreateSetter(type, field.FieldType, field);
getters.Add(field, getDelegate);
setters.Add(field, setDelegate);
}
m_packetFieldGetters.Add(type, getters);
m_packetFieldSetters.Add(type, setters);
}
private Delegate CreateGetter(Type classType, Type getReturnType, FieldInfo field)
{
string methodName = field.ReflectedType.FullName + ".get_" + field.Name;
Type[] parameterTypes = new Type[1] { classType };
DynamicMethod getterMethod = new DynamicMethod(methodName, getReturnType, parameterTypes, true);
ILGenerator gen = getterMethod.GetILGenerator();
if (field.IsStatic)
{
gen.Emit(OpCodes.Ldsfld, field);
}
else
{
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Ldfld, field);
}
gen.Emit(OpCodes.Ret);
// Create the specific Func<,> instance
Type[] typeArgs = new Type[] { classType, getReturnType };
Type generic = typeof(Func<,>);
Type genInstance = generic.MakeGenericType(typeArgs);
Delegate getterDelegate = getterMethod.CreateDelegate(genInstance);
return getterDelegate;
}
private Delegate CreateSetter(Type classType, Type setValueType, FieldInfo field)
{
string methodName = field.ReflectedType.FullName + ".set_" + field.Name;
Type[] parameters = new Type[2]
{
classType,
setValueType
};
DynamicMethod setterMethod = new DynamicMethod(methodName, null, parameters);
ILGenerator gen = setterMethod.GetILGenerator();
if (field.IsStatic)
{
gen.Emit(OpCodes.Ldarg_1);
gen.Emit(OpCodes.Stsfld, field);
}
else
{
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Ldarg_1);
gen.Emit(OpCodes.Stfld, field);
}
gen.Emit(OpCodes.Ret);
// Create the specific Action<,> instance
Type[] typeArgs = new Type[] { classType, setValueType };
Type generic = typeof(Action<,>);
Type genInstance = generic.MakeGenericType(typeArgs);
Delegate ret = setterMethod.CreateDelegate(genInstance);
return ret;
}
}
}
// THIS IS IN A DIFERENT ASSEMBLY
namespace MirrorNetTesting
{
// This is just an example packet
public class StudentPacket : UserPacket
{
public int age;
public int height;
public double grades;
public string firstName;
public string lastName;
}
class Program
{
static void Main(string[] args)
{
Assembly asm = Assembly.GetAssembly(typeof(StudentPacket));
MirrorNetManager.Instance.InitializePackets(asm);
PerformanceTesting();
Console.ReadLine();
}
public static void PerformanceTesting()
{
int studentsCount = 1000 * 100;
StudentPacket[] studentsArray = new StudentPacket[studentsCount];
//////////////////////////////////////////////////////////////////////////
Random rnd = new Random();
for (int i = 0; i < studentsArray.Length; i++)
{
StudentPacket student = new StudentPacket();
student.age = rnd.Next();
student.height = rnd.Next();
student.grades = rnd.NextDouble();
student.firstName = "First " + rnd.Next().ToString();
student.lastName = "Last " + rnd.Next().ToString();
studentsArray[i] = student;
}
var fieldsArray = typeof(StudentPacket).GetFields().ToArray();
//////////////////////////////////////////////////////////////////////////
// Begin normal getter test
Console.WriteLine("Testing normal getters");
Stopwatch normalGetterSw = new Stopwatch();
normalGetterSw.Start();
foreach (var student in studentsArray)
{
//object getValue;
var getAge = student.age;
var getHeight = student.height;
var getGrades = student.grades;
var getFirstName = student.firstName;
var getLastName = student.lastName;
}
normalGetterSw.Stop();
//////////////////////////////////////////////////////////////////////////
// Begin reflection getter test
Console.WriteLine("Testing reflection getters");
Stopwatch reflectionGetterSw = new Stopwatch();
reflectionGetterSw.Start();
foreach (var student in studentsArray)
{
object getValue;
for (int i = 0; i < fieldsArray.Length; i++)
{
FieldInfo field = fieldsArray[i];
getValue = MirrorNetManager.Instance.GetValue(student, field);
}
}
reflectionGetterSw.Stop();
//////////////////////////////////////////////////////////////////////////
// Begin normal setter test
Console.WriteLine("Testing normal setters");
Stopwatch normalSetterSw = new Stopwatch();
int age = 10;
int height = 12;
double grades = 1432.523d;
string firstName = "first name";
string lastName = "last name";
normalSetterSw.Start();
foreach (var student in studentsArray)
{
student.age = age;
student.height = height;
student.grades = grades;
student.firstName = firstName;
student.lastName = lastName;
}
normalSetterSw.Stop();
//////////////////////////////////////////////////////////////////////////
// Begin reflection setter test
Console.WriteLine("Testing reflection setters ");
Stopwatch reflectionSetterSw = new Stopwatch();
object[] setValues = new object[]
{
age,
height,
grades,
firstName,
lastName
};
reflectionSetterSw.Start();
foreach (var student in studentsArray)
{
for (int i = 0; i < fieldsArray.Length; i++)
{
FieldInfo field = fieldsArray[i];
MirrorNetManager.Instance.SetValue(student, field, setValues[i]);
}
}
reflectionSetterSw.Stop();
//////////////////////////////////////////////////////////////////////////
Console.WriteLine("Normal getter: \t {0}", normalGetterSw.ElapsedMilliseconds);
Console.WriteLine("Normal setter: \t {0}", normalSetterSw.ElapsedMilliseconds);
Console.WriteLine("Reflection getter: \t {0}", reflectionGetterSw.ElapsedMilliseconds);
Console.WriteLine("Reflection setter: \t {0}", reflectionSetterSw.ElapsedMilliseconds);
//////////////////////////////////////////////////////////////////////////
}
}
}
輸出（相關的東西只）：
Normal getter: 3
Normal setter: 4
Reflection getter: 261
Reflection setter: 183
反思getter和setter實際上是動態調用，他們通常最終以300毫秒。
此外，由於代碼相當長，我也發佈了它here也。
謝謝。我專注於使代碼更好地執行，實際上我忘記了它的目的。 – dburner