// recursive method
public static MemberBinding[] AssembleSelectMembers <TEntity, TModel>(
List <PropertyInfo> modelProperties, List <MemberBinding> memberBindings, ParameterExpression parameter)
{
if (modelProperties.Count > 0)
{
PropertyInfo property = modelProperties.First();
modelProperties.RemoveAt(0);
List <string> entityPropertyPath = ObjectInspector.RetrieveGridEntityPropertyPath(property);
// initiate recursive method
Expression entityProperty =
AssembleProperty(
Expression.MakeMemberAccess(parameter, typeof(TEntity).GetProperty(entityPropertyPath.First())),
entityPropertyPath.Skip(1).ToList());
MemberAssignment modelPropertyBind = Expression.Bind(
typeof(TModel).GetProperty(property.Name), entityProperty);
memberBindings.Add(modelPropertyBind);
return(AssembleSelectMembers <TEntity, TModel>(modelProperties, memberBindings, parameter));
}
return(memberBindings.ToArray());
}
public static Expression TransformDateString(Expression entityProperty)
{
UnaryExpression nullableEntityDate = Expression.Convert(entityProperty, typeof(DateTime?));
MethodInfo concatStringMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) });
MethodInfo dateNameMethod = ObjectInspector.GetSqlFunctionDateTimeMethodInfo("DateName");
var datePart = Expression.Call(dateNameMethod, Expression.Constant("dd"), nullableEntityDate);
Expression transformPredicate = Expression.Add(datePart, Expression.Constant("/"), concatStringMethod);
MethodInfo datePartMethod = ObjectInspector.GetSqlFunctionDateTimeMethodInfo("DatePart");
MethodInfo stringConvertMethod = ObjectInspector.GetSqlFunctionStringConvertMethod(typeof(double?));
// original month from 'MM' gives the name of the month. Therefore, do SqlFunctions.StringConvert((double)'MM')
// to extract digits
datePart = Expression.Call(
stringConvertMethod,
Expression.Convert(Expression.Call(datePartMethod, Expression.Constant("MM"), nullableEntityDate), typeof(Nullable <double>)));
transformPredicate = Expression.Add(transformPredicate, datePart, concatStringMethod);
transformPredicate = Expression.Add(transformPredicate, Expression.Constant("/"), concatStringMethod);
datePart = Expression.Call(dateNameMethod, Expression.Constant("yyyy"), nullableEntityDate);
transformPredicate = Expression.Add(transformPredicate, datePart, concatStringMethod);
return(transformPredicate);
}
public static Expression <Func <TEntity, TModel> > GetSelectClause <TEntity, TModel>()
{
ParameterExpression parameter = Expression.Parameter(typeof(TEntity), "entity");
List <PropertyInfo> properties = ObjectInspector.ExtractGridModelSelectProperties <TModel>();
MemberBinding[] modelMembers =
AssembleSelectMembers <TEntity, TModel>(properties, new MemberBinding[] { }.ToList(), parameter);
NewExpression newModelItem = Expression.New(typeof(TModel));
MemberInitExpression init = Expression.MemberInit(newModelItem, modelMembers);
return((Expression <Func <TEntity, TModel> >)Expression.Lambda(init, parameter));
}
public static Expression TransformTimeString(Expression entityProperty)
{
UnaryExpression nullableEntityTime = Expression.Convert(entityProperty, typeof(TimeSpan?));
MethodInfo concatStringMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) });
MethodInfo dateNameMethod = ObjectInspector.GetSqlFunctionDateTimeMethodInfo("DateName");
var datePart = Expression.Call(dateNameMethod, Expression.Constant("hh"), nullableEntityTime);
Expression transformPredicate = Expression.Add(datePart, Expression.Constant(":"), concatStringMethod);
datePart = Expression.Call(dateNameMethod, Expression.Constant("mi"), nullableEntityTime);
transformPredicate = Expression.Add(transformPredicate, datePart, concatStringMethod);
transformPredicate = Expression.Add(transformPredicate, Expression.Constant(":"), concatStringMethod);
datePart = Expression.Call(dateNameMethod, Expression.Constant("ss"), nullableEntityTime);
transformPredicate = Expression.Add(transformPredicate, datePart, concatStringMethod);
return(transformPredicate);
}
