Class QueryExecuterHelper

A helper class for common functions using QueryableExecuters

Inheritance

System.Object

QueryExecuterHelper

Inherited Members

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

System.Object.ToString()

Namespace: LemonEdge.Utils

Assembly: Utils.dll

Syntax

public static class QueryExecuterHelper

Methods

FilterItems<T>(IEnumerable<T>, QueryableFilter)

Applies a QueryableFilter to a collection of items

Declaration

public static IEnumerable<T> FilterItems<T>(this IEnumerable<T> items, QueryableFilter filter)

Parameters

Type	Name	Description
System.Collections.Generic.IEnumerable<T>	items	The collection of items to apply a filter to
QueryableFilter	filter	The filter to apply to a collection of items

Returns

Type	Description
System.Collections.Generic.IEnumerable<T>	Only the items that match the specified filter

Type Parameters

Name	Description
T	The type of items in the collection

MergeQueryResults<T>(QueryableExecuter, (List<T> NewItems, List<T> UpdatedItems, List<T> DeletedItems), IQueryable, IEnumerable<T>, IEqualityComparer<T>)

Merges a set of results from a QueryableExecuter with the local new, updated and deleted items. Takes account of any paging state on the items too

Declaration

public static IEnumerable<T> MergeQueryResults<T>(this QueryableExecuter items, (List<T> NewItems, List<T> UpdatedItems, List<T> DeletedItems) localItems, IQueryable localMergedItems, IEnumerable<T> externalResults, IEqualityComparer<T> comparer)

Parameters

Type	Name	Description
QueryableExecuter	items	The QueryableExecuter that holds all the filtering information that was applied to the external result set
System.ValueTuple<System.Collections.Generic.List<T>, System.Collections.Generic.List<T>, System.Collections.Generic.List<T>>	localItems	All the New, Updated, and Deleted items held locally of the same type
System.Linq.IQueryable	localMergedItems	The new and Updated items merged together with the QueryableExecuter filtering applied
System.Collections.Generic.IEnumerable<T>	externalResults	The set of data returned from executing the QueryableExecuter against the database
System.Collections.Generic.IEqualityComparer<T>	comparer	A comparer to ensure duplicate items are eliminated. i.e. if the external results contains an item that is modified locally we want to keep the local modified version

Returns

Type	Description
System.Collections.Generic.IEnumerable<T>	The external result items merged with the local items according to any paging requirements of the QueryableExecuter

Type Parameters

Name	Description
T	The type of items being merged

ToSingleFilter(IEnumerable<QueryableFilter>, GroupType)

Takes a collection of filters and creates a new one with the specified groupBy logical operator applied to the collection of filters as children

Declaration

public static QueryableFilter ToSingleFilter(this IEnumerable<QueryableFilter> filters, GroupType groupBy)

Parameters

Type	Name	Description
System.Collections.Generic.IEnumerable<QueryableFilter>	filters	The set of filters to be child filters for the newly created QueryableFilter
GroupType	groupBy	The logical operator to apply to all the child filters

Returns

Type	Description
QueryableFilter	A new QueryableFilter with the specified filters as children

Remarks

For instance takes the filters (XXX Equals 123), (YYY NotEquals 456) and when applied with the operator OR returns ((XXX Equals 123) OR (YYY NotEquals 456))