public FilterOperatorAttribute(FilterOperatorViewModel oper, string dbField = null)
{
this.Operator = oper;
this.DbField = dbField;
}
public static IQueryable <T> ProcessDinamicQuery <T, P>(
this IQueryable <T> source, GridRequestViewModel <P> requestModel, char propertyNavigationSplitter = '_') where P : new()
{
var query = source;
bool isSorted = false;
foreach (var aProperty in requestModel.Search.PredicateObject.GetType().GetProperties())
{
if (aProperty.GetValue(requestModel.Search.PredicateObject) == null)
{
continue;
}
var param = Expression.Parameter(typeof(T), "p");
if (typeof(P).GetProperty(aProperty.Name, BindingFlags.IgnoreCase | BindingFlags.Public | BindingFlags.Instance).PropertyType == typeof(string))
{
string[] props = aProperty.Name.Split(propertyNavigationSplitter);
if (!PropertyExists <T>(props[0]))
{
continue;
}
Type type = typeof(T);
ParameterExpression arg = Expression.Parameter(type, "x");
Expression expr = arg;
foreach (string prop in props)
{
PropertyInfo pi = type.GetProperty(prop);
expr = Expression.Property(expr, pi);
type = pi.PropertyType;
}
var attr = (FilterOperatorAttribute[])aProperty.GetCustomAttributes(typeof(FilterOperatorAttribute), false);
if (attr.Length > 0)
{
if (!string.IsNullOrEmpty(attr[0].DbField))
{
expr = Expression.Property(arg, attr[0].DbField);
}
}
var value = Expression.Constant(aProperty.GetValue(requestModel.Search.PredicateObject));
var containsmethod = type.GetMethod("Contains", new[] { typeof(string) });
var call = Expression.Call(expr, containsmethod, value);
var lambda = Expression.Lambda <Func <T, bool> >(call, arg);
query = query.Where(lambda);
}
else
{
string[] props = aProperty.Name.Split(propertyNavigationSplitter);
if (!PropertyExists <T>(props[0]))
{
continue;
}
Type type = typeof(T);
ParameterExpression arg = Expression.Parameter(type, "x");
Expression expr = arg;
foreach (string prop in props)
{
PropertyInfo pi = type.GetProperty(prop);
expr = Expression.Property(expr, pi);
type = pi.PropertyType;
}
var value = Expression.Constant(aProperty.GetValue(requestModel.Search.PredicateObject));
FilterOperatorViewModel _operator = FilterOperatorViewModel.Equals;
var attr = (FilterOperatorAttribute[])aProperty.GetCustomAttributes(typeof(FilterOperatorAttribute), false);
if (attr.Length > 0)
{
if (attr[0].Operator != null)
{
_operator = attr[0].Operator.Value;
}
if (!string.IsNullOrEmpty(attr[0].DbField))
{
expr = Expression.Property(arg, attr[0].DbField);
}
}
if (typeof(P).GetProperty(aProperty.Name, BindingFlags.IgnoreCase | BindingFlags.Public | BindingFlags.Instance).PropertyType == typeof(DateTime?))
{
var dateVal = ((DateTime)aProperty.GetValue(requestModel.Search.PredicateObject)).AddDays(1).AddTicks(-1);
if (_operator == FilterOperatorViewModel.GreaterOrEquals)
{
dateVal = dateVal.AddDays(-1);
}
value = Expression.Constant(dateVal);
}
BinaryExpression binaryExpression = Expression.Equal(Expression.Property(arg, aProperty.Name), value);
if (_operator == FilterOperatorViewModel.GreaterOrEquals)
{
binaryExpression = Expression.GreaterThanOrEqual(Expression.Property(arg, aProperty.Name), value);
}
if (_operator == FilterOperatorViewModel.LessOrEquals)
{
binaryExpression = Expression.LessThanOrEqual(Expression.Property(arg, aProperty.Name), value);
}
var exp = Expression.Lambda <Func <T, bool> >(binaryExpression, arg);
query = query.Where(exp);
}
}
if (!string.IsNullOrEmpty(requestModel.Sort.Predicate))
{
isSorted = true;
if (requestModel.Sort.Reverse)
{
query = query.OrderByDescending(requestModel.Sort.Predicate);
}
else
{
query = query.OrderBy(requestModel.Sort.Predicate);
}
}
if (!isSorted)
{
query = query.OrderBy("Id");
}
return(query);
}
