feat(Table): add OverscanCount parameter

src/BootstrapBlazor.Server/Locales/en-US.json

@@ -4885,7 +4885,7 @@
     "Affix": "Affix",
     "Watermark": "Watermark",
     "OctIcon": "Oct Icons",
-    "UniverIcons": "Univer Icons",
+    "UniverIcon": "Univer Icons",
     "Typed": "Typed",
     "UniverSheet": "UniverSheet"
   },

src/BootstrapBlazor/Components/Table/Table.razor

@@ -369,13 +369,13 @@
             {
                 @if (Items != null)
                 {
-                    <Virtualize ItemSize="RowHeight" OverscanCount="10" Items="@Items.ToList()" ChildContent="RenderRow">
+                    <Virtualize ItemSize="RowHeight" OverscanCount="@OverscanCount" Items="@Items.ToList()" ChildContent="RenderRow">
                     </Virtualize>
                 }
                 else
                 {
                     <Virtualize @ref="_virtualizeElement"
-                                ItemSize="RowHeight" OverscanCount="10" Placeholder="RenderPlaceholderRow"
+                                ItemSize="RowHeight" OverscanCount="@OverscanCount" Placeholder="RenderPlaceholderRow"
                                 ItemsProvider="LoadItems" ItemContent="RenderRow">
                     </Virtualize>
                 }

src/BootstrapBlazor/Components/Table/Table.razor.Edit.cs

@@ -484,7 +484,7 @@ protected async Task QueryData(bool triggerByPagination = false)
         else
         {
             ResetSelectedRows(Items);
-            RowsCache = null;
+            _rowsCache = null;
         }
         return;
 
@@ -513,7 +513,7 @@ async Task OnQuery(QueryPageOptions queryOption)
             }
 
             // 更新数据后清除缓存防止新数据不显示
-            RowsCache = null;
+            _rowsCache = null;
             return;
 
             void ProcessData()

src/BootstrapBlazor/Components/Table/Table.razor.Toolbar.cs

@@ -648,7 +648,7 @@ protected async Task<bool> SaveModelAsync(EditContext context, ItemChangedType c
         if (DynamicContext != null)
         {
             await DynamicContext.SetValue(context.Model);
-            RowsCache = null;
+            _rowsCache = null;
             valid = true;
         }
         else
@@ -1095,7 +1095,7 @@ private void ResetDynamicContext()
 
     private void QueryDynamicItems(QueryPageOptions queryOption, IDynamicObjectContext? context)
     {
-        RowsCache = null;
+        _rowsCache = null;
         if (context != null)
         {
             var items = context.GetItems();

src/BootstrapBlazor/Components/Table/Table.razor.TreeNode.cs

@@ -28,7 +28,6 @@ public partial class Table<TItem>
     /// <summary>
     /// 获得/设置 树形数据集合
     /// </summary>
-    [NotNull]
     private List<TableTreeNode<TItem>> TreeRows { get; } = new(100);
 
     /// <summary>
@@ -107,7 +106,7 @@ protected Func<Task> ToggleTreeRow(TItem item) => async () =>
                 IsLoadChildren = false;
 
                 // 清除缓存
-                RowsCache = null;
+                _rowsCache = null;
 
                 // 更新 UI
                 StateHasChanged();
@@ -121,6 +120,7 @@ private async Task<IEnumerable<IExpandableNode<TItem>>> GetChildrenRowAsync(Tabl
         {
             throw new InvalidOperationException(NotSetOnTreeExpandErrorMessage);
         }
+
         return await OnTreeExpand(node.Value);
     }
 }

src/BootstrapBlazor/Components/Table/Table.razor.cs

@@ -370,6 +370,13 @@ private string GetSortTooltip(ITableColumn col) => SortName != col.GetFieldName(
     [Parameter]
     public float RowHeight { get; set; } = 38f;
 
+    /// <summary>
+    /// Gets or sets the overscan count for virtual scrolling. Default is 10.
+    /// </summary>
+    /// <remarks>Effective when <see cref="ScrollMode"/> is set to <see cref="ScrollMode.Virtual"/>.</remarks>
+    [Parameter]
+    public int OverscanCount { get; set; } = 10;
+
     [Inject]
     [NotNull]
     private IOptionsMonitor<BootstrapBlazorOptions>? Options { get; set; }
@@ -928,7 +935,7 @@ protected override void OnParametersSet()
             IsPagination = false;
         }
 
-        RowsCache = null;
+        _rowsCache = null;
 
         if (IsExcel)
         {
@@ -1267,7 +1274,7 @@ protected async Task LoopQueryAsync()
     private IEnumerable<TItem> QueryItems { get; set; } = [];
 
     [NotNull]
-    private List<TItem>? RowsCache { get; set; }
+    private List<TItem>? _rowsCache = null;
 
     /// <summary>
     /// 获得 当前表格所有 Rows 集合
@@ -1279,8 +1286,8 @@ public List<TItem> Rows
             // https://gitee.com/LongbowEnterprise/BootstrapBlazor/issues/I5JG5D
             // 如果 QueryItems 无默认值
             // 页面 OnInitializedAsync 二刷再 OnAfterRender 过程中导致 QueryItems 变量为空 ToList 报错
-            RowsCache ??= IsTree ? TreeRows.GetAllItems() : [.. (Items ?? QueryItems)];
-            return RowsCache;
+            _rowsCache ??= IsTree ? TreeRows.GetAllItems() : [.. (Items ?? QueryItems)];
+            return _rowsCache;
         }
     }
 

test/UnitTest/Components/TableTest.cs

@@ -2104,6 +2104,7 @@ public void IsFixedFooter_Ok()
                 pb.Add(a => a.RenderMode, TableRenderMode.Table);
                 pb.Add(a => a.ScrollMode, ScrollMode.Virtual);
                 pb.Add(a => a.RowHeight, 39.5f);
+                pb.Add(a => a.OverscanCount, 10);
                 pb.Add(a => a.ShowFooter, true);
                 pb.Add(a => a.IsFixedFooter, true);
                 pb.Add(a => a.Items, Foo.GenerateFoo(localizer));