Limit # of items that can be selected

[Roger]

Is there a way to limit the number of items that can be selected in a MultiSelect component?

[Svetoslav Dimitrov]

Hello Roger,

Yes, you can limit the total count of selected items in several ways:

• Use if / else statement to limit the Count (Below you can see a code snippet)
• In the following article, you will find two other approaches: https://docs.telerik.com/blazor-ui/knowledge-base/multiselect-always-select-item-limit-total:
  • you can control what gets added to the list with your own code through the component events
  • you can use forms validation to prevent form submission and easily show messages to the user

Of course, you can combine the three approaches.

Code snippet for if / else statement:

• This code snippet will show you how to limit the Count property of the C# List
• Render the component if the Count is below certain amount
• Render a custom message / component if the Count is over the predefined amount
  

 

<h4 class="text-info">Select multiple data</h4>

@if (MySelectedItems.Count < MaximumNumberOfItems)
{
    <TelerikMultiSelect Data="@Options" @bind-Value="@MySelectedItems" />
}
else
{
    <div class="alert alert-danger">You cannot select more items</div>
}

@if (MySelectedItems?.Count > 0)
{
    <ul>
        @foreach (int item in MySelectedItems)
        {
            <li class="text-muted">@item</li>
        }
    </ul>
}

@code {
    int MaximumNumberOfItems = 5;
    List<int> MySelectedItems { get; set; } = new List<int>();
    List<int> Options { get; set; } = Enumerable.Range(1, 20).ToList();
}

 

Regards,
Svetoslav Dimitrov
Progress Telerik

 UI for Blazor