检查是否有任何WPF DataGrid单元格有错误

I have validation set up on the cells and it works as expected (placing a red highlight around the textbox and adding a tooltip with the error). However, If I try to access Validation.GetHasError(TheGrid) where TheGrid is my DataGrid, it is always false. Does anyone know how to check if ANY cells in the DataGrid have errors?I have validation set up on the cells and it wo