/// <summary>
/// Applies the given DynamicQueryOptions to the generic IEnumerable instace.
/// </summary>
/// <param name="currentSet">Existing IEnumerable instance.</param>
/// <param name="dynamicQueryOptions">Query options to apply.</param>
/// <returns>DynamicQueryOptions applied IEnumerable instance,</returns>
public static IQueryable ApplyFilters(this IQueryable currentSet, DynamicQueryOptions dynamicQueryOptions)
{
try
{
if (dynamicQueryOptions == null || currentSet == null)
{
return(currentSet);
}
Expression exp = null;
// Create the query parameter
ParameterExpression param = Expression.Parameter(currentSet.ElementType, currentSet.ElementType.Name.ToLower());
if (dynamicQueryOptions.Filters != null && dynamicQueryOptions.Filters.Count > 0)
{
// Copy the array since we need to mutate it, we should avoid mutating the real list.
List <Filter> dqbFilters = dynamicQueryOptions.Filters.ToList();
// Since the expression is null at this point, we should create it with our first filter.
exp = BuildFilterExpression(param, dqbFilters.FirstOrDefault(), dynamicQueryOptions.UsesCaseInsensitiveSource);
dqbFilters.RemoveAt(0); // Remove the first since it was added already.
// Append the rest
foreach (Filter item in dqbFilters)
{
exp = Expression.AndAlso(exp, BuildFilterExpression(param, item, dynamicQueryOptions.UsesCaseInsensitiveSource));
}
}
if (dynamicQueryOptions.SortOptions != null && dynamicQueryOptions.SortOptions.Count > 0)
{
List <OrderOptionDetails> orderLambdas = new List <OrderOptionDetails>();
foreach (SortOption so in dynamicQueryOptions.SortOptions)
{
Expression paramExpr = ExtractMember(param, so.PropertyName);
orderLambdas.Add(new OrderOptionDetails
{
Direction = so.SortingDirection,
Expression = Expression.Lambda(paramExpr, param),
ParameterExpression = paramExpr,
CaseSensitive = so.CaseSensitive
});
}
var orderVisitor = new OrderFunctionVisitor(
currentSet.Expression,
orderLambdas,
currentSet.ElementType,
dynamicQueryOptions.UsesCaseInsensitiveSource,
dynamicQueryOptions.IgnorePredefinedOrders);
currentSet = currentSet.Provider.CreateQuery(orderVisitor.ApplyOrders());
}
if (exp != null)
{
MethodCallExpression whereFilter = Expression.Call(
LINQUtils.BuildLINQExtensionMethod(
nameof(Enumerable.Where),
genericElementTypes: new[] { currentSet.ElementType },
enumerableType: typeof(Queryable)),
currentSet.Expression,
Expression.Quote(Expression.Lambda(exp, param)));
currentSet = currentSet.Provider.CreateQuery(whereFilter);
}
if (dynamicQueryOptions.PaginationOption != null)
{
if (dynamicQueryOptions.PaginationOption.AssignDataSetCount)
{
dynamicQueryOptions.PaginationOption.DataSetCount = (int)_countFunction.Invoke(null, new[] { currentSet });
}
if (dynamicQueryOptions.PaginationOption.Offset > 0)
{
MethodCallExpression skip = Expression.Call(
_skipFunction,
currentSet.Expression,
Expression.Constant(dynamicQueryOptions.PaginationOption.Offset));
currentSet = currentSet.Provider.CreateQuery(skip);
}
if (dynamicQueryOptions.PaginationOption.Count > 0)
{
MethodCallExpression take = Expression.Call(
_takeFunction,
currentSet.Expression,
Expression.Constant(dynamicQueryOptions.PaginationOption.Count));
currentSet = currentSet.Provider.CreateQuery(take);
}
}
return(currentSet);
}
catch (Exception ex)
{
throw new DynamicQueryException("DynamicQueryBuilder has encountered an unhandled exception", string.Empty, ex);
}
}
/// <summary>
/// Applies the given DynamicQueryOptions to the generic IEnumerable instace.
/// </summary>
/// <param name="currentSet">Existing IEnumerable instance.</param>
/// <param name="dynamicQueryOptions">Query options to apply.</param>
/// <returns>DynamicQueryOptions applied IEnumerable instance,</returns>
public static IQueryable ApplyFilters(this IQueryable currentSet, DynamicQueryOptions dynamicQueryOptions)
{
try
{
if (dynamicQueryOptions == null || currentSet == null)
{
return(currentSet);
}
Expression exp = null;
// Create the query parameter (x =>)
ParameterExpression param = Expression.Parameter(currentSet.ElementType, currentSet.ElementType.Name.ToLower());
// Check if we have any filters
if (dynamicQueryOptions.Filters != null && dynamicQueryOptions.Filters.Count > 0)
{
// Lets build the first expression and then iterate the rest and append them to this one
exp = BuildFilterExpression(param,
dynamicQueryOptions.Filters.First(),
dynamicQueryOptions.UsesCaseInsensitiveSource);
// We start to iterate with the second element here because we have just built the first expression up above
for (int i = 1; i < dynamicQueryOptions.Filters.Count; ++i)
{
// Build the current expression
Expression builtExpression = BuildFilterExpression(param,
dynamicQueryOptions.Filters[i],
dynamicQueryOptions.UsesCaseInsensitiveSource);
// Get the previous filter to retrieve the logical operator between the current and the next filter
Filter previousFilter = dynamicQueryOptions.Filters.ElementAtOrDefault(i - 1);
exp = LINQUtils.BuildLINQLogicalOperatorExpression(previousFilter, exp, builtExpression);
}
}
if (dynamicQueryOptions.SortOptions != null && dynamicQueryOptions.SortOptions.Count > 0)
{
var orderLambdas = new List <OrderOptionDetails>();
foreach (SortOption so in dynamicQueryOptions.SortOptions)
{
Expression paramExpr = ExtractMember(param, so.PropertyName, false);
orderLambdas.Add(new OrderOptionDetails
{
Direction = so.SortingDirection,
Expression = Expression.Lambda(paramExpr, param),
ParameterExpression = paramExpr,
CaseSensitive = so.CaseSensitive
});
}
var orderVisitor = new OrderFunctionVisitor(
currentSet.Expression,
orderLambdas,
currentSet.ElementType,
dynamicQueryOptions.UsesCaseInsensitiveSource,
dynamicQueryOptions.IgnorePredefinedOrders);
currentSet = currentSet.Provider.CreateQuery(orderVisitor.ApplyOrders());
}
if (exp != null)
{
MethodCallExpression whereFilter = Expression.Call(
LINQUtils.BuildLINQExtensionMethod(
nameof(Enumerable.Where),
genericElementTypes: new[] { currentSet.ElementType },
enumerableType: typeof(Queryable)),
currentSet.Expression,
Expression.Quote(Expression.Lambda(exp, param)));
currentSet = currentSet.Provider.CreateQuery(whereFilter);
}
if (dynamicQueryOptions.PaginationOption != null)
{
if (dynamicQueryOptions.PaginationOption.AssignDataSetCount)
{
dynamicQueryOptions.PaginationOption.DataSetCount = (int)ExtensionMethods.CountFunction.Invoke(null, new[] { currentSet });
}
if (dynamicQueryOptions.PaginationOption.Offset > 0)
{
MethodCallExpression skip = Expression.Call(
ExtensionMethods.SkipFunction,
currentSet.Expression,
Expression.Constant(dynamicQueryOptions.PaginationOption.Offset));
currentSet = currentSet.Provider.CreateQuery(skip);
}
if (dynamicQueryOptions.PaginationOption.Count > 0)
{
MethodCallExpression take = Expression.Call(
ExtensionMethods.TakeFunction,
currentSet.Expression,
Expression.Constant(dynamicQueryOptions.PaginationOption.Count));
currentSet = currentSet.Provider.CreateQuery(take);
}
}
return(currentSet);
}
catch (Exception ex)
{
throw new DynamicQueryException("DynamicQueryBuilder has encountered an unhandled exception", string.Empty, ex);
}
}
