public static Expression <Func <TEntity, bool> > Parse <TEntity>(IDataFilter dataFilter, DataFilterMetaInfo filterInfo, Expression node)
{
ObjectChecker.CheckNotNull(filterInfo);
var filterFields = filterInfo.FilterFields;
if (filterFields.Count == 0)
{
return((Expression <Func <TEntity, bool> >)node);
}
// filter
var body = node;
foreach (var filterField in filterFields)
{
var handler = FilterFieldHandlerFactory.GetHandler(filterField.FilterFieldType);
if (handler != null)
{
// call FilterFieldHandler
body = handler.Handle(body, filterField);
}
}
// 删除 {True}
var optimizer = new ExprTreeOptimizer(body);
body = optimizer.Optimize();
return(body as Expression <Func <TEntity, bool> >);
}
public static void ShoutDown()
{
FilterFieldHandlerFactory.Clear();
FieldExprNameMappingFactory.Clear();
GC.Collect();
}
internal static void Reset()
{
FilterFieldHandlerFactory.Reset();
FieldExprNameMappingFactory.Clear();
}
/// <summary>
/// Add 一个自定义字段的处理Handler
/// </summary>
/// <typeparam name="TFilterFieldHandler"></typeparam>
/// <param name="filterFiledHandlerFunc"></param>
public static void AddFilterFieldHandler <TFilterFieldHandler>(Func <TFilterFieldHandler> filterFiledHandlerFunc)
where TFilterFieldHandler : class, IFilterFieldHandler
{
FilterFieldHandlerFactory.Register(filterFiledHandlerFunc);
}
