Highlight GridView row when a condition is met

Yes, add OnRowDataBound="yourGridview_RowDataBound" to your gridview. This event gets triggered for every gridview row.

In the code behind, have this:

public void yourGridview_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        // do your stuffs here, for example if column risk is your third column:
        if (e.Row.Cells[2].Text == "high")
        {
            e.Row.BackColor = Color.Red;
        }
    }
}

Use RowDataBound Event. In this event you would get to add the css based upon your condition

 void GridView_RowDataBound(Object sender, GridViewRowEventArgs e)
  {

    if(e.Row.RowType == DataControlRowType.DataRow)
    {
      // Logic for High
      if(e.Row.Cells[1].Text > 100)
      //set color
      e.Row.Attributes.Add("style", "this.style.backgroundColor = '#FFFFFF';");

    }

  }