From fb6ecd0600288eea757bea63a8d3a60107a159b6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bar=C4=B1=C5=9F=20Can=20Y=C4=B1lmaz?=
 <30300440+bariscanyilmaz@users.noreply.github.com>
Date: Wed, 1 Mar 2023 17:46:23 +0300
Subject: [PATCH] give more details about list service filtering

---
 docs/en/UI/Angular/List-Service.md | 35 ++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/docs/en/UI/Angular/List-Service.md b/docs/en/UI/Angular/List-Service.md
index fc3697bd35..5301222ca1 100644
--- a/docs/en/UI/Angular/List-Service.md
+++ b/docs/en/UI/Angular/List-Service.md
@@ -201,3 +201,38 @@ You may use observables in combination with [AsyncPipe](https://angular.io/guide
 
 <input type="text" name="search" [(ngModel)]="list.filter">
 ```
+ABP doesn't have a built-in filtering mechanism. You need to implement yourself and handle `filter` property in backend as seen in below. 
+
+```cs
+public class BookRequestDto : PagedAndSortedResultRequestDto
+{
+  public string Filter { get; set; }
+}
+```
+```cs
+public interface IBookAppService :
+    ICrudAppService< //Defines CRUD methods
+        BookDto, //Used to show books
+        Guid, //Primary key of the book entity
+        BookRequestDto, //Used for paging/sorting
+        CreateUpdateBookDto> //Used to create/update a book
+{
+
+}
+```
+```cs
+//Override GetListAsync in BookAppService
+
+public override async Task<PagedResultDto<BookDto>> GetListAsync(BookRequestDto input)
+{
+  var query=await ReadOnlyRepository.GetQueryableAsync();
+  query.WhereIf(!string.IsNullOrEmpty(input.Filter),x=>x.Name.Contains(input.Filter));
+
+  var totalCount = await AsyncExecuter.CountAsync(query);
+  var items = await AsyncExecuter.ToListAsync(query);
+  var entities = ObjectMapper.Map<List<Book>, List<BookDto>>(items);
+
+  return new PagedResultDto<BookDto>(totalCount,entities);
+}
+
+```
\ No newline at end of file