public Expression?CreateExpression(IOvBuilderContext builderContext)
{
var items = builderContext.OfType <T>().ToArray();
if (items.Any())
{
var inputType = builderContext.OfType <SourceObjectOvBuilderContextItem>()
.First()
.InputType;
var extendType = builderContext.OfType <ExtendObjectOvBuilderContextItem>()
.FirstOrDefault()
?.ExtendObjectType;
var exps = CreateExpressions();
if (items.Length == 1)
{
return(exps.Single());
}
var pExp = Expression.Parameter(inputType, "s");
if (extendType != null)
{
var sourceExp = Expression.Parameter(extendType, "e");
var blockItems = exps.Select(x => Expression.Invoke(x, pExp, sourceExp));
var blockExpression = Expression.Block(blockItems);
var actionType = Expression.GetActionType(inputType, extendType);
var finalExp = Expression.Lambda(actionType, blockExpression, pExp, sourceExp);
return(finalExp);
}
else
{
var blockItems = exps.Select(x => Expression.Invoke(x, pExp));
var blockExpression = Expression.Block(blockItems);
var actionType = Expression.GetActionType(inputType);
var finalExp = Expression.Lambda(actionType, blockExpression, pExp);
return(finalExp);
}
IEnumerable <Expression> CreateExpressions()
{
foreach (var item in items)
{
yield return(CreateCore(inputType, extendType, item));
}
}
}
return(null);
}
public Expression?CreateExpression(IOvBuilderContext builderContext)
{
var item = builderContext.OfType <T>().LastOrDefault();
if (item != null)
{
var inputType = builderContext.OfType <SourceObjectOvBuilderContextItem>()
.First()
.InputType;
var extendType = builderContext.OfType <ExtendObjectOvBuilderContextItem>()
.FirstOrDefault()
?.ExtendObjectType;
return(CreateCore(inputType, extendType, item));
}
return(null);
}
internal static bool TryGetContextItem <TItem>(this IOvBuilderContext builderContext,
out TItem?obj)
where TItem : class
{
var item = builderContext.OfType <TItem>().FirstOrDefault();
if (item != null)
{
obj = item;
return(true);
}
obj = default !;