private object DelegateProxy(Type delegateType, ICallRouter callRouter)
{
var delegateMethodToProxy = delegateType.GetMethod("Invoke");
var proxyParameterTypes = delegateMethodToProxy.GetParameters().Select(x => new ParameterInfoWrapper(x)).ToArray();
var delegateCall = new DelegateCall(callRouter, delegateMethodToProxy.ReturnType, proxyParameterTypes);
var invokeOnDelegateCall = delegateCall.MethodToInvoke;
ParameterExpression[] proxyParameters = delegateMethodToProxy.GetParameters().Select(x => Expression.Parameter(x.ParameterType, x.Name)).ToArray();
Expression[] proxyParametersAsObjects = proxyParameters.Select(x => (Expression)Expression.Convert(x, typeof(object))).ToArray();
Expression callInvokeOnDelegateCallInstance =
Expression.Call(
Expression.Constant(delegateCall),
invokeOnDelegateCall,
new Expression[]
{
Expression.NewArrayInit(typeof(object), proxyParametersAsObjects)
}
);
if (delegateMethodToProxy.ReturnType != typeof(void))
{
callInvokeOnDelegateCallInstance =
Expression.Convert(callInvokeOnDelegateCallInstance, delegateMethodToProxy.ReturnType);
}
var proxyExpression = Expression.Lambda(delegateType, callInvokeOnDelegateCallInstance, proxyParameters);
return(proxyExpression.Compile());
}
private object DelegateProxy(Type delegateType, ICallRouter callRouter)
{
var delegateMethodToProxy = delegateType.GetMethod("Invoke");
var proxyParameterTypes = delegateMethodToProxy.GetParameters().Select(x => new ParameterInfoWrapper(x)).ToArray();
var delegateCall = new DelegateCall(callRouter, delegateType, delegateMethodToProxy.ReturnType, proxyParameterTypes);
var invokeOnDelegateCall = delegateCall.MethodToInvoke;
ParameterExpression[] proxyParameters = delegateMethodToProxy.GetParameters().Select(x => Expression.Parameter(x.ParameterType, x.Name)).ToArray();
Expression[] proxyParametersAsObjects = proxyParameters.Select(x => (Expression)Expression.Convert(x, typeof(object))).ToArray();
var bodyExpressions = new List <Expression>();
bool isVoid = delegateMethodToProxy.ReturnType == typeof(void);
var arguments = Expression.Variable(typeof(object[]), "arguments");
var result = isVoid ? null : Expression.Variable(delegateMethodToProxy.ReturnType, "result");
bodyExpressions.Add(Expression.Assign(arguments, Expression.NewArrayInit(typeof(object), proxyParametersAsObjects)));
Expression callInvokeOnDelegateCallInstance = Expression.Call(Expression.Constant(delegateCall), invokeOnDelegateCall, arguments);
if (!isVoid)
{
callInvokeOnDelegateCallInstance = Expression.Assign(result, Expression.Convert(callInvokeOnDelegateCallInstance, delegateMethodToProxy.ReturnType));
}
bodyExpressions.Add(callInvokeOnDelegateCallInstance);
for (var index = 0; index < proxyParameters.Length; index++)
{
var parameter = proxyParameters[index];
if (parameter.IsByRef)
{
var assignment = Expression.Assign(parameter, Expression.Convert(Expression.ArrayAccess(arguments, Expression.Constant(index)), parameter.Type));
bodyExpressions.Add(assignment);
}
}
if (!isVoid)
{
bodyExpressions.Add(result);
}
var variables = isVoid ? new[] { arguments } : new[] { arguments, result };
var proxyExpression = Expression.Lambda(delegateType, Expression.Block(variables, bodyExpressions), proxyParameters);
return(proxyExpression.Compile());
}
