private Func <object, JsValue[], object> CreateInvoker(MethodInfo method)
{
var methodParameters = method.GetParameters();
var expressionParamThis = Expression.Parameter(typeof(object), "clrThis");
var expressionParamArgs = Expression.Parameter(typeof(JsValue[]), "jsArgs");
var arguments =
methodParameters.Select((x, idx) => {
if (x.GetCustomAttribute <ParamArrayAttribute>() != null)
{
var getItemExpression =
Expression.Call(GetType(), nameof(Slice), new Type[0], expressionParamArgs, Expression.Constant(idx));
return(_converter.CreateConverterExpr(x.ParameterType, getItemExpression, expressionParamThis, false));
}
else
{
var getItemExpression = (Expression)Expression.ArrayAccess(expressionParamArgs, Expression.Constant(idx));
return
(Expression.Condition(
Expression.LessThan(Expression.Constant(idx),
Expression.ArrayLength(expressionParamArgs)),
_converter.CreateConverterExpr(x.ParameterType, getItemExpression, expressionParamThis,
method.GetInterfaceDeclarationsForMethod().Any(p =>
p.GetParameters()[idx].GetCustomAttribute <JsExpandArrayAttribute>() != null)),
Expression.Convert(
x.HasDefaultValue
? Expression.Constant(x.DefaultValue)
: Expression.Constant(GetDefault(x.ParameterType)),
x.ParameterType)
));
}
}).ToArray();
var expressionCall = Expression.Call(
Expression.Convert(expressionParamThis, method.DeclaringType),
method,
arguments);
if (method.ReturnParameter.ParameterType == typeof(void))
{
var act = Expression.Lambda <Action <object, JsValue[]> >(
expressionCall,
expressionParamThis,
expressionParamArgs).Compile();
return((clrThis, jsArgs) => { act(clrThis, jsArgs); return null; });
}
var invoker = Expression.Lambda <Func <object, JsValue[], object> >(
Expression.Convert(expressionCall, typeof(object)),
expressionParamThis,
expressionParamArgs).Compile();
return(invoker);
}
private static Action <object, JsValue> CreateSetter(DomConverter converter, PropertyInfo property)
{
var expThisArg = Expression.Parameter(typeof(object), "clrThis");
var expValueArg = Expression.Parameter(typeof(JsValue), "jsValue");
var setterExpression =
Expression.Assign(
Expression.Property(Expression.Convert(expThisArg, property.DeclaringType), property),
converter.CreateConverterExpr(property.PropertyType, expValueArg, expThisArg));
var setterLambda = Expression.Lambda <Action <object, JsValue> >(setterExpression, expThisArg, expValueArg)
.Compile();
return(setterLambda);
}
