if子句在datagridviewimagecolumn中使用image

Example:
If current row image = "Red.png"... show error msg  
If current row image = "Green.png"... Insert to database

(dataGridView1[2, 2] as DataGridViewImageCell).Description = "Red";// Or Green

foreach (DataGridViewRow row in dataGridView1.Rows)
{
  if(row.Cells[2] is DataGridViewImageCell)
  {
     if((row.Cells[2] as DataGridViewImageCell).Description == "Red")
     { // your stuff}
  }
}