GDS.XLSX

Use this package to easily (and fast) export a DataTable to Excel (XLSX)
This component is Lightweight

  class Program
  {

    static void Main(string[] args)
    {
      // get some data to work with
      // Load DataTable (usally this comes from SQL, but here we load it from binary serialized datatable)
      //DataTable dt = GDS.XLSX.DataTableHelper.LoadDataTableFromBinary(@"D:\dt\c48242bad49f49899a139714c97a0790");

      DataTable dt = new DataTable("SomeTable");
      dt.Columns.Add("Product Name", typeof(string));
      dt.Columns.Add("Downloads", typeof(int));
      dt.Columns.Add("Freeware", typeof(bool));
      dt.Rows.Add("Easy Poster Printer", 1_427_144, false);
      dt.Rows.Add("Shield Defender", 450, true);

      /********************************************************************************
       * THE SIMPLEST SOLUTION 
       ********************************************************************************/


      // Step 1. Create an instance of XLSXGenerator
      GDS.XLSX.XLSXGenerator xlsx = new GDS.XLSX.XLSXGenerator();

      // Step 2. Save the xlsx document
      xlsx.SaveXLSX(dt, System.IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop),"myfile.xlsx"));

      // Step 3. There is no step 3!

      // done



      /********************************************************************************
       * The build in class helper for DataTable:
       ********************************************************************************/

      // Get a DataTable bytes
      //var arr = GDS.XLSX.DataTableHelper.GetDataTableToBytes(dt);

      // Save DataTable to file.
      //System.IO.File.WriteAllBytes(@"D:\dt\c48242bad49f49899a139714c97a0790", arr);


      /********************************************************************************
       * The more advanced example, with custom rendering etc.
       *********************************************************************************/

      xlsx.HeaderBold = true;     // set column header bold (default is true)
      xlsx.HeaderVisible = true; // set if header should be shown at all (default is true)

      // Column Render
      xlsx.OnColumnHeaderRender += (ref string columnHeaderText, int columnIndex, ref bool bold)=>
      {
        // explic change column header text, and bold-strategy pr. column
        if (columnHeaderText == "Downloads")
        {
          columnHeaderText = "* Downloads *";
          //bold = false;
        }
      };
      
      // Cell Render
      xlsx.OnCellRender += (int rowIndex, int columnIndex, ref Type dataType, ref object data, ref bool suppress) =>
      {
        // change cell rendering strategy (suppress or/and alter data and data type)
        if (dataType == typeof(bool))
        {
          dataType = typeof(string);
          data = ((bool)data) ? "Yes" : "No";
        }
      };
      
      // Row Render
      xlsx.OnRowRender += (int rowIndex, ref bool skip) => 
      {
        // change row render strategy (skip) - If you want to skip specific rows for some reason
        // Example: skip = (rowIndex % 2 == 0);
      };

      /********************************************************************************
       * SAVING THE DOCUMENT (Several ways to do it, depending on your needs)
       ********************************************************************************/


      // save to file
      xlsx.SaveXLSX(dt, System.IO.Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "myfile2.xlsx"));

      // save to Stream
      //using (MemoryStream stream = new MemoryStream())
      //{
      //  xlsx.SaveXLSX(dt, stream);
      //  System.IO.File.WriteAllBytes(@"d:\dt\test2-mem-stream.xlsx", stream.ToArray());
      //}

      // get bytes
      //var bytes = xlsx.GetXLXSBytes(dt);
      //System.IO.File.WriteAllBytes(@"d:\dt\test3-bytes.xlsx", bytes);
    }
  }