The DialogHost. Show() method affects the rendering speed of the UI when multiple rows are selected in the DataGrid

Bug explanation

After using the DialogHost. Show() method, if multiple rows (over 10000 rows) are selected in the DataGrid, it will seriously affect the rendering speed of the UI. At present, I have found this issue on many computers. If the DataGrid data exceeds tens of thousands of rows, when performing a select all operation, the UI may even lag for more than ten seconds. The same amount of data results in a fast rendering speed before using the DialogHost. Show() method. Visual Studio performance probe analysis was used and it was found that the stuck time was used for GC.

Version

4.9.0

DialogHost.Show() と 10,000 行を超える行を含む WPF DataGrid で遅延を再現し、ダイアログを表示する前後でのすべて選択の動作を比較します。Visual Studio のパフォーマンス プロファイラーを使用して、GC に関連するレンダリング遅延を確認します。大量選択の操作で、報告されている数秒間の UI 遅延が発生しなくなれば完了です。