Won't Fix
Last Updated: 16 Apr 2020 09:31 by ADMIN
Scheduled for 2.11.0
Created on: 20 Jan 2020 14:32
Category: Grid
Type: Bug Report
Two way binding using @bind-SelectedItems throwing Error: System.ArgumentNullException: Value cannot be null.

A workaround is to initialize the collection of the selected items:

<TelerikButton OnClick="@LoadData">Load Data</TelerikButton>

<TelerikGrid Data=@adminUsers Height="300px" Pageable=true PageSize=10 SelectionMode="@GridSelectionMode.Multiple"
        <GridCheckboxColumn SelectAll="true"></GridCheckboxColumn>
        <GridColumn Field=@nameof(User.DisplayName) Title="User Name" />
        <GridColumn Field=@nameof(User.Department) Title="Department" />
        <GridColumn Field=@nameof(User.Status) Title="Status" />
        <GridColumn Field=@nameof(User.EmployeeId) Title="Employee Id" />


    public IEnumerable<User> SelectedAdminUsers { get; set; } = Enumerable.Empty<User>();

    public List<User> adminUsers { get; set; }

    void LoadData()
        adminUsers = Enumerable.Range(1, 200).Select(x => new User
            EmployeeId = x,
            Status = $"status {x}",
            Department = $"department {x}",
            DisplayName = $"name {x}"

    public class User
        public string DisplayName { get; set; }
        public string Department { get; set; }
        public string Status { get; set; }
        public int EmployeeId { get; set; }

1 comment
Marin Bratanov
Posted on: 16 Apr 2020 09:31

Hello Manoj,

You should initialize the SelectedItems collections. The documentation has been updated to showcase this (both for single and multiple selection).


Marin Bratanov
Progress Telerik

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