How Can LINQ Group a List of Objects into Nested Lists?

Group list of objects into nested lists using LINQ

Efficient data organization is crucial in the field of programming. LINQ provides a powerful mechanism for grouping objects based on specific conditions. This article will solve a common problem: grouping a list of objects into a new list containing nested lists.

Consider the following class definition:

<code>public class User
{
    public int UserID { get; set; }
    public string UserName { get; set; }
    public int GroupID { get; set; }
}</code>

In order to group users based on their GroupID, we can utilize the following code:

<code>var groupedCustomerList = userList
    .GroupBy(u => u.GroupID)
    .Select(grp => grp.ToList())
    .ToList();</code>

Code interpretation:

1. GroupBy: This clause divides the original user list into multiple groups based on the GroupID attribute.
2. Select: It then converts each result (i.e. a set of users with the same GroupID) into a list of users.
3. ToList: Finally, the result is converted into a new list of nested lists, each nested list containing users from the same group.

This LINQ expression cleverly groups the original list of users by GroupID, presenting them in an organized manner. Each nested list in the final result represents a group of users sharing the same GroupID.

The above is the detailed content of How Can LINQ Group a List of Objects into Nested Lists?. For more information, please follow other related articles on the PHP Chinese website!