C# List collection Contains invalid problem

Others 2021-03-07 16:43:00 views: null

I changed the bug today and encountered a strange problem. The entity object was clearly added to the collection, but List.Contains(entity); just didn't work.

Find a way to replace it temporarily

bool flag = list.Exists(o => o.Id == entity.Id);
if (!flag)
{
    list.Add(entity);
｝

Who has studied it and hopes to let me know.

Guess you like

Origin blog.csdn.net/qq_41630695/article/details/114443255

C# List collection Contains invalid problem

List containsKey and Map contains determine whether the collection contains a value

C# Convert DataTable to List<> Generic Collection

C# generic collection and non-generic collection (List ArrayLIst)

The Android list contains the problem of disordered state when scrolling with checkboxes

C # generic collection of - list

Processing method string [HTML] html rendering contains invalid HTML tags, HTML tags string that contains the problem to be solved escaped

Solve the problem that the workflow in dolphinscheduler-3.1.3 contains chunjun tasks, and the parameter invalid is displayed when saving and cannot be saved

Generic collection class List<T> of C# data structure

[C# Basic Intensive Lecture] The use of List collection

c# collection in the collection

Array base class in C#, ArrayList ordered collection, Dictionary generics, Hashtable and List collection value assignment

C# List object collection is reorganized into a new collection and a field is obtained to form a new array or string to separate

ERROR 1055 (42000): Expression # 1 of SELECT list is not in GROUP BY clause and contains nonaggregated ...... error solutions to the problem!

Mysql met Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggre problem solving

Ordered collection problem in Java in Java List Set Map if ordered CONCLUSIONS

Android Problem Collection (13)-Error: Tag <manifest> attribute package has invalid character'"'.

Collection --- list

Collection --List

Collection and List

List of Collection

List collection

C# List (DataTable, ArrayList, Dictionary) collection Linq to Entity Lamda grouping and summing and averaging

SELECT list is not in GROUP BY clause and contains

The contains() method of java to deduplicate List

C # dictionary, collection, time complexity of the list

Collection: Collection, List, Set

[C #] basic collection - Stack Stack list LinkList ordered list SortedList

Unity3d C# uses the Sequence of the DOTween plug-in to implement a series of animation OnComplete invalid and color setting invalid problem records

Recommended

Ranking

error: (-215:Assertion failed) !_img.empty() in function ‘cv::imwrite‘

Database migration between Navicat servers

Minimum number of rotation of the array: Array

balenaEtcher for mac (make a boot disk software) v1.5.67

Custom processing serialization and deserialization in jackson

Mu-en-mask system development software

Mastering Regular Expressions

Find mileage Java--

Web pages can not directly concern the public micro-channel number how to do? A key to arouse public concern number of micro-channel solutions

[CodeForces - 739B] Alyona and a tree Tree + [difference] + bipartite

Daily

2024-05-12(28)

2024-05-11(32)

2024-05-10(34)

2024-05-09(32)

2024-05-08(18)

2024-05-07(34)

2024-05-06(6)

2024-05-05(0)

2024-05-04(18)

2024-05-03(8)