/// <summary>
/// Validates orderby string and constructs SortInformation object. If not valid returns null.
/// </summary>
/// <param name="orderBy"></param>
/// <param name="validOrderByOptions"></param>
/// <returns>If order is not valid null, otherwise insatnce of <see cref="SortInformation"/></returns>
protected SortInformation ParseOrderBy(string orderBy, string validOrderByOptions)
{
if (string.IsNullOrWhiteSpace(orderBy))
{
return(null);
}
SortInformation sortInformation = GetSortInformation(orderBy);
if (validOrderByOptions.Contains(sortInformation.PropertyName))
{
return(sortInformation);
}
return(null);
}
public override IQueryable <Contact> SetUpSorting(IQueryable <Contact> query)
{
SortInformation sortInformation = ParseOrderBy(OrderBy, ValidOrderByValues);
if (sortInformation == null)
{
return(query);
}
switch (sortInformation.PropertyName)
{
case "name":
query = ApplyOrdering(query, s => s.Name, sortInformation.SortDirection);
break;
case "address":
query = ApplyOrdering(query, s => s.Address, sortInformation.SortDirection);
break;
}
return(query);
}
private SortInformation GetSortInformation(string orderby)
{
SortInformation sortInformation;
if (orderby.StartsWith("-"))
{
sortInformation = new SortInformation
{
PropertyName = orderby.Substring(1, orderby.Length - 1),
SortDirection = ListSortDirection.Descending
};
}
else
{
sortInformation = new SortInformation
{
PropertyName = orderby,
SortDirection = ListSortDirection.Ascending
};
}
return(sortInformation);
}