查找特定行是否包含选定（突出显示）的单元格

At the moment, I've created a loop which runs through every cells in my datagridview to find if any cells are selected (highlighted), and if so that cell's row/ column header backcolor changes. The problem I have with this is that once the row and column count start to become a large amount, I start experiencing lag. So I wondering does anybody know a way of instantly being able to find whether a row or column contains a selected or highlighted cell without using a loop.At the moment, I've created a loop which runs t