how to get cell background color of excel using C#?

Question

I want to retrieve the background color of cell of excel using c# but I just can't find a way to do it

1. which library shall I use ? microsoft.office.tools.excel.workbook.aspx or microsoft.office.interop.excel ? what's the differents?

2. I have tried following code but get no luck:

   using Excel = Microsoft.Office.Interop.Excel;
   
   private void button1_Click(object sender, EventArgs e)
   {
       ofd.Filter = "xlsx|*.xlsx|xls|*.xls";
   
       if(ofd.ShowDialog() == DialogResult.OK)
       {
           textBox2.Text = ofd.FileName;
           Excel.Application excel = new Excel.Application();
           Excel.Workbook wb = excel.Workbooks.Open(textBox2.Text);
           Excel.Worksheet ws = wb.Sheets[1];
           Excel.Range xlRange = ws.Cells[0, 0];
           Debug.WriteLine("===" + xlRange.Interior.Color);
       }
   }
   

Answer 1

There is nice lib called EPPlus, that makes your relationships with excel much easier. You can find it on NuGet.
So use this code to get color:

var x = sheet.Cells[rowIndex, colIndex].Style.Fill.BackgroundColor;

And this to set color:

sheet.Cells[rowIndex, colIndex].Style.Fill.SetCellsColor( Color.Yellow );

Answer 2

Easiest solution what-so-ever :

 private void Get_Colors()
  {
      Excel.Workbook excel = Globals.ThisAddIn.Application.ActiveWorkbook;
      Excel.Worksheet sheet = null;
      Excel.Range ran = sheet.UsedRange;
      for (int x = 1; x <= ran.Rows.Count; x++)
      {
          for (int y = 1; y <= ran.Columns.Count; y++)
          {
              string CellColor = sheet.Cells[x, y].Interior.Color.ToString(); //Here I go double value which is converted to string.
              if (sheet.Cells[x, y].Value != null && (CellColor == Color.Transparent.ToArgb().ToString() || **CellColor == Excel.XlRgbColor.rgbGold.GetHashCode().ToString()**))
              {
                  sheet.Cells[x, y].Interior.Color = Color.Transparent;
              }
          }
      }
  }