public UpdateWithSignature <T> GetGenerator <T>(MethodBase updateMethod)
{
if (updateMethod == null)
{
throw new ArgumentNullException("updateMethod");
}
var updateMethodDetails = new UpdateMethodSummary <T>(updateMethod);
var cachedGenerator = _cache.GetIfAvailable <T>(updateMethodDetails.DeclaringType, updateMethodDetails.UpdateArguments);
if (cachedGenerator != null)
{
return(cachedGenerator);
}
// In this case, the delegate has a single updateValues reference - an array of update values (so argsIsAnArray is true
var sourceParameter = Expression.Parameter(typeof(T), "source");
var argsParameter = Expression.Parameter(typeof(object[]), "args");
var argsIsAnArray = true;
var generator
= Expression.Lambda <UpdateWithSignature <T> >(
GetGeneratorBodyExpression <T>(updateMethodDetails.UpdateArguments, sourceParameter, new[] { argsParameter }, argsIsAnArray),
sourceParameter,
argsParameter
)
.Compile();
_cache.Set <T>(updateMethodDetails.DeclaringType, updateMethodDetails.UpdateArguments, generator);
return(generator);
}
public TUpdateSignature GetUncachedGeneratorExpression <TUpdateSignature>(MethodBase updateMethod, int numberOfUpdateArguments)
{
if (updateMethod == null)
{
throw new ArgumentNullException("updateMethod");
}
if (numberOfUpdateArguments <= 0)
{
throw new ArgumentOutOfRangeException("must be greater than zero", "numberOfUpdateArguments");
}
// In this case, the delegate will have one concrete argument per update value (as opposed to a single argument that is an array
// of update values), so argsIsAnArray is false)
var updateMethodDetails = new UpdateMethodSummary <TSource>(updateMethod);
var sourceParameter = Expression.Parameter(typeof(TSource), "source");
var argParameters = Enumerable.Range(0, numberOfUpdateArguments)
.Select(i => Expression.Parameter(typeof(object), "arg" + i))
.ToArray(); // Call ToArray() to evaluate this once otherwise the reference won't match when used twice below
var argsIsAnArray = false;
return
(Expression.Lambda <TUpdateSignature>(
_updateWitHelper.GetGeneratorBodyExpression <TSource>(updateMethodDetails.UpdateArguments, sourceParameter, argParameters, argsIsAnArray),
new[] { sourceParameter }.Concat(argParameters)
)
.Compile());
}
