public ProxyByImplementationType(ModuleEmitter moduleEmitter, Type serviceType, Type implementationType, ServiceLifetime lifetime)
{
this.moduleEmitter = moduleEmitter;
this.serviceType = serviceType;
this.implementationType = implementationType;
this.lifetime = lifetime;
}
private RuntimeModule EmitAndSaveModule(string name, BoundStatementBlock body)
{
ModuleEmitter emitter = new ModuleEmitter(body);
RuntimeModule module = new RuntimeModule(name, emitter.Instructions, body.Syntax);
this.Modules.Add(module.Name, module);
return(module);
}
public void Test1()
{
#if NET461
var m = new ModuleEmitter(true);
#else
var m = new ModuleEmitter();
#endif
var classType = m.DefineType("test", TypeAttributes.Public);
var method = classType.DefineMethod("Test", MethodAttributes.Public, typeof(int));
var pI = method.DefineParameter(typeof(int), ParameterAttributes.None, "i");
var pJ = method.DefineParameter(typeof(int), ParameterAttributes.None, "j");
var b = Variable(typeof(Expression));
method.Append(Assign(b, Constant(GetExpression(entry => entry.Id))));
var switchAst = Switch(Constant(1));
switchAst.Case(Constant(1))
.Append(IncrementAssign(pI));
switchAst.Case(Constant(2))
.Append(AddAssign(pI, Constant(5)));
var constantAst2 = Constant(1, typeof(object));
var switchAst2 = Switch(constantAst2);
var stringAst = Variable(typeof(string));
var intAst = Variable(typeof(int));
switchAst2.Case(stringAst);
switchAst2.Case(intAst)
.Append(Assign(pI, intAst));
var switchAst3 = Switch(Constant("ABC"), DecrementAssign(pI), typeof(void));
switchAst3.Case(Constant("A"))
.Append(IncrementAssign(pI));
switchAst3.Case(Constant("B"))
.Append(AddAssign(pI, Constant(5)));
method.Append(switchAst)
.Append(switchAst2)
.Append(switchAst3)
.Append(Return(Condition(GreaterThanOrEqual(pI, pJ), pI, pJ)));
var type = classType.CreateType();
#if NET461
m.SaveAssembly();
#endif
}
/// <summary>
/// 使用拦截器。
/// 为标记了 <see cref="InterceptAttribute"/> 的接口、类或方法生成代理类。
/// </summary>
/// <param name="services">服务集合。</param>
/// <returns></returns>
public static IServiceCollection UseMiddleware(this IServiceCollection services)
{
if (services is null)
{
throw new ArgumentNullException(nameof(services));
}
#if NET40_OR_GREATER && DEBUG
var moduleEmitter = new ModuleEmitter(true);
#else
var moduleEmitter = new ModuleEmitter();
#endif
for (int i = 0; i < services.Count; i++)
{
ServiceDescriptor descriptor = services[i];
if (!Intercept(descriptor))
{
continue;
}
IProxyByPattern byPattern;
if (descriptor.ImplementationType is null)
{
if (descriptor.ImplementationInstance is null)
{
byPattern = new ProxyByInstance(moduleEmitter, descriptor.ServiceType, descriptor.ImplementationInstance);
}
else
{
byPattern = new ProxyByFactory(moduleEmitter, descriptor.ServiceType, descriptor.ImplementationFactory, descriptor.Lifetime);
}
}
else
{
byPattern = new ProxyByImplementationType(moduleEmitter, descriptor.ServiceType, descriptor.ImplementationType, descriptor.Lifetime);
}
services[i] = byPattern.Resolve();
}
#if NET40_OR_GREATER && DEBUG
moduleEmitter.SaveAssembly();
#endif
return(services);
}
public ProxyByServiceType(ModuleEmitter moduleEmitter, Type serviceType, ServiceLifetime lifetime)
{
this.moduleEmitter = moduleEmitter;
this.serviceType = serviceType;
this.lifetime = lifetime;
}
public ProxyByInstance(ModuleEmitter moduleEmitter, Type serviceType, object instance) : base(moduleEmitter, serviceType, ServiceLifetime.Singleton)
{
this.instance = instance ?? throw new ArgumentNullException(nameof(instance));
}
public ProxyByFactory(ModuleEmitter moduleEmitter, Type serviceType, Func <IServiceProvider, object> implementationFactory, ServiceLifetime lifetime) : base(moduleEmitter, serviceType, lifetime)
{
this.implementationFactory = implementationFactory ?? throw new ArgumentNullException(nameof(implementationFactory));
}
public void TestLinq()
{
#if NET461
var m = new ModuleEmitter(true);
#else
var m = new ModuleEmitter();
#endif
var classType = m.DefineType("linq", TypeAttributes.Public);
var method = classType.DefineMethod("Query", MethodAttributes.Public, typeof(void));
var pI = method.DefineParameter(typeof(int), ParameterAttributes.None, "i");
var pJ = method.DefineParameter(typeof(int), ParameterAttributes.None, "j");
var type = typeof(Entry);
var arg = Variable(typeof(ParameterExpression));
var argProperty = Variable(typeof(MemberExpression));
var callArg = Call(typeof(Expression).GetMethod(nameof(Expression.Parameter), new Type[] { typeof(Type) }), Constant(type));
var callProperty = Call(typeof(Expression).GetMethod(nameof(Expression.Property), new Type[] { typeof(Expression), typeof(string) }), arg, Constant("Id"));
//var callBlock = Call(typeof(Expression).GetMethod(nameof(Expression.Block), new Type[] { typeof(IEnumerable<ParameterExpression>), typeof(IEnumerable<Expression>) }));
method.Append(Assign(arg, callArg));
method.Append(Assign(argProperty, callProperty));
var variable_variables = Variable(typeof(ParameterExpression[]));
var variables = NewArray(1, typeof(ParameterExpression));
method.Append(Assign(variable_variables, variables));
method.Append(Assign(ArrayIndex(variable_variables, 0), arg));
var constantI = Call(typeof(Expression).GetMethod(nameof(Expression.Constant), new Type[] { typeof(object) }), Convert(pI, typeof(object)));
var equalMethod = Call(typeof(Expression).GetMethod(nameof(Expression.Equal), new Type[] { typeof(Expression), typeof(Expression) }), argProperty, constantI);
var lamdaMethod = typeof(Tests).GetMethod(nameof(Tests.Lambda))
.MakeGenericMethod(typeof(Func <Entry, bool>));
var whereLambda = Variable(typeof(Expression <Func <Entry, bool> >));
method.Append(Assign(whereLambda, Call(lamdaMethod, equalMethod, variable_variables)));
method.Append(ReturnVoid());
classType.CreateType();
#if NET461
m.SaveAssembly();
#endif
// 生成代码如下：
/**
* public void Query(int i, int j)
* {
* ParameterExpression parameterExpression = Expression.Parameter(typeof(Entry));
* MemberExpression left = Expression.Property(parameterExpression, "Id");
* Expression<Func<Entry, bool>> expression = Tests.Lambda<Func<Entry, bool>>(parameters: new ParameterExpression[1]
* {
* parameterExpression
* }, body: Expression.Equal(left, Expression.Constant(i)));
* }
*/
}
