如何在foreach循环中比较内部linq查询

Question

In this foreach loop, I want to find my model with this Condition you see. The problem is I can't compare b.GroupId and group.GroupId it says b.GroupId is null but the group.GroupId is not null I have traced it and it has a value of 1. This is my code

@foreach (var group in groups.Where(g => g.ParrentId == null))
{
    <div class="tab-pane active animated fadeInRight" id="tab_@group.GroupId">
    var blog = Model.First(b=>b.GroupId==group.GroupId);
}

my model

@model IEnumerable<DataLayer.Entities.Blog.Blog>

@inject Core.Services.Interfaces.IGroupServices _groupServices;
@{ 
List<DataLayer.Entities.Group.Group> groups = 
_groupServices.getAllGroups();}
 

as you see group.GroupId is 1 but 'a' is still 0 this is an example of my problem

Answer 1

but the group .GroupId is not null

But as you stated the issues is with b , not with group . So somewhere in your model there is GroupId with null. It is unclear how to fix that since there are no information about your Model. But maybe something like this will help:

Model.First(b=>b.GroupId!=null && b.GroupId==group.GroupId);