Setting KeyField for Grid

[vieledinge]

Hello,

I have a Blazor Bootstrap Grid with many data records. The data comes from an MS SQL View via EF Core. Various tables are joined in the view.

<Grid Id="serviceOrdersGrid"
              Data="_serviceOrders"
              TItem="ServiceOrdersOverview"
              KeyField="TempGuid"
              AllowSorting="true"
              AllowFiltering="@_userSetting.ViewSettings.ShowFilterRow"
              AllowPaging="@_userSetting.ViewSettings.UsePaging"
              AutoHidePaging="true"
              AllowRowClick="true"
              PageSize="@_userSetting.ViewSettings.PageSize"
              Responsive="false"
              Class="table table-hover border-top"
              HeaderRowCssClass="bg-primary text-white bg-opacity-75 border-bottom-0"
              FiltersRowCssClass="bg-secondary text-white bg-opacity-25 border-bottom-0"
              FiltersTranslationProvider="GridFiltersTranslationProvider"
              PaginationItemsTextFormat="Einträge {0} - {1} von {2} Einträgen"
              EmptyText="Keine Daten zu den aktuellen Kriterien gefunden!"
              RowClass="GetGridRowClass"
              OnRowClick="OnGridRowClick">

</Grid>

When using the grid, the following error occurs:

System.InvalidOperationException: More than one sibling of element 'tr' has the same key value, '14975999'. Key values must be unique.
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.ThrowExceptionForDuplicateKey(Object key, RenderTreeFrame& frame)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.BuildKeyToInfoLookup(DiffContext diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForFramesWithSameSequence(DiffContext& diffContext, Int32 oldFrameIndex, Int32 newFrameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForFramesWithSameSequence(DiffContext& diffContext, Int32 oldFrameIndex, Int32 newFrameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForFramesWithSameSequence(DiffContext& diffContext, Int32 oldFrameIndex, Int32 newFrameIndex)
   at Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiffBuilder.AppendDiffEntriesForRange(DiffContext& diffContext, Int32 oldStartIndex, Int32 oldEndIndexExcl, Int32 newStartIndex, Int32 newEndIndexExcl)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment, Exception& renderFragmentException)
   at Microsoft.AspNetCore.Components.RenderTree.Renderer.ProcessRenderQueue()

How can I tell the grid which column/property to use for the key? KeyField="TempGuid" doesnt work.

I have already added an extra column (SELECT NEWID() AS TempGuid, ...) to the view in order to have a unique key value.

Any Ideas?

[ZippyNeuron]

I know this OP is quite old but I'll answer this anyway, as I hit this very problem myself today.

I believe the issue is due to the Grid relying on object.GetHashCode() to arrive at row (TR) "uniqueness". It's widely understood that GetHashCode() is not truly unique and sometimes there can be collisions with other objects that form a dataset. I believe that's what we're seeing here.

I visited the GitHub code for the Grid and found that you can override the default key assignment by using the grid RowKeySelector attribute. For example ...

On my object I have an Id, which is a primary key and an identity column. I assigned my own key on the grid with.

<Grid RowKeySelector="(o) => o.Id" />

Hope this helps someone somewhere,

Andy.