Blazor Sortable

An implementation of the SortableJS library for Blazor. This example shows you how to reorder elements within a list using drag and drop.

View Demos

Prerequisites

• dotnet 7

Running Locally

1. Clone this repository.
2. Run the project using dotnet watch.

How to use it in your own project

1. Add SortableJS to your index.html file. You can either download from the SortableJS website or use a CDN...

    <script src="https://cdnjs.cloudflare.com/ajax/libs/Sortable/1.13.0/Sortable.min.js"></script>
   

2. Add the SortableList.razor, SortableList.razor.css and SortableList.razor.js files to your project.

3. Add the SortableList component to your page and define the SortableItemTemplate...

    <SortableList Id="sortable" Items="items" OnUpdate="@SortList" Context="item">
        <SortableItemTemplate>
            <div>
                <p>@item.Name</p>
            </div>
        </SortableItemTemplate>
    </SortableList>
   

• Items: The list of items to be displayed. Can be of any type.
• OnUpdate: The method to be called when the list is updated.
• Context: The name of the variable to be used in the template.

The SortableItemTemplate can contain any markup or components that you want.

API

Properties

All proerties are optional and have default values.

Id: String (Default: GUID): The id of the HTML element that will be turned into a sortable. If you don't supply this, a random id (GUID) will be generated for you.

Group: String (Default: null) - Used for dragging between lists. Set the group to the same value on both lists to enable.

Pull: String (Default: null) - Used when you want to clone elments into a list instead of moving them. Set Pull to "clone".

Put: Boolean (Default: True) - Set to false to disable dropping from another list onto the current list.

Sort: Boolean (Default: True) - Disable sorting within a list by setting to false.

Handle (Default: ""): The CSS class you want the sortable to respect as the drag handle.

Filter (Default: ""): The CSS class you want to use to identify elements that cannot be sorted or moved.

Methods

OnUpdate (Optional): The method to be called when the list is updated. You can name this method whatever you like, but it expects a oldIndex and newIndex parameters when the drag and drop occurs.

OnRemove (Optional): The method to be called when an item is removed from a list. This method is useful for handling the drop even between multiple lists. Like OnUpdate, it expects oldIndex and newIndex parameters.

You will need to handle all events yourself. If you don't handle any events, no sort or move will happen as Blazor needs to make the changes to the underlying data structures so it can re-render the list.

Here is an example of how to reorder your list when the OnUpdate is fired...

private void SortList((int oldIndex, int newIndex) indices)
{
    var (oldIndex, newIndex) = indices;

    var items = this.items;
    var itemToMove = items[oldIndex];
    items.RemoveAt(oldIndex);

    if (newIndex < items.Count)
    {
        items.Insert(newIndex, itemToMove);
    }
    else
    {
        items.Add(itemToMove);
    }

    StateHasChanged();
}