C# Excel : Correct way to get Rows and Columns count

Question

I have problem with C# Interop Excel get valid range with big file

https://www.dropbox.com/s/betci638b1faw8g/Demo%20Training%20Data.xlsx?dl=0

This is my fi

Answer 1

I would use this approach to get the Rows and Columns count which will return the result of the cells which are not empty.

// Find the last real row
lastUsedRow = worksheet.Cells.Find("*",System.Reflection.Missing.Value, 
                               System.Reflection.Missing.Value, System.Reflection.Missing.Value, 
                               Excel.XlSearchOrder.xlByRows,Excel.XlSearchDirection.xlPrevious, 
                               false,System.Reflection.Missing.Value,System.Reflection.Missing.Value).Row;

// Find the last real column
lastUsedColumn = worksheet.Cells.Find("*", System.Reflection.Missing.Value, 
                               System.Reflection.Missing.Value,System.Reflection.Missing.Value, 
                               Excel.XlSearchOrder.xlByColumns,Excel.XlSearchDirection.xlPrevious, 
                               false,System.Reflection.Missing.Value,System.Reflection.Missing.Value).Column;

Here is the complete code for your reference:

using Excel = Microsoft.Office.Interop.Excel;

Excel.Application xlApp     = null;
Excel.Workbook wb           = null;
Excel.Worksheet worksheet   = null;
int lastUsedRow             = 0;
int lastUsedColumn          = 0;
string srcFile              = @"Path to your XLSX file";

xlApp = new Excel.ApplicationClass();
xlApp.Visible = false;
wb = xlApp.Workbooks.Open(srcFile,
                               0, false, 5, "", "", false, Excel.XlPlatform.xlWindows, "",
                               true, false, 0, true, false, false);

worksheet = (Excel.Worksheet)wb.Worksheets[1];
Excel.Range range

// Find the last real row
lastUsedRow = worksheet.Cells.Find("*",System.Reflection.Missing.Value, 
                               System.Reflection.Missing.Value, System.Reflection.Missing.Value, 
                               Excel.XlSearchOrder.xlByRows,Excel.XlSearchDirection.xlPrevious, 
                               false,System.Reflection.Missing.Value,System.Reflection.Missing.Value).Row;

// Find the last real column
lastUsedColumn = worksheet.Cells.Find("*", System.Reflection.Missing.Value, 
                               System.Reflection.Missing.Value,System.Reflection.Missing.Value, 
                               Excel.XlSearchOrder.xlByColumns,Excel.XlSearchDirection.xlPrevious, 
                               false,System.Reflection.Missing.Value,System.Reflection.Missing.Value).Column;

xlApp.Workbooks.Close();
xlApp.Quit();

Marshal.ReleaseComObject(worksheet);
Marshal.ReleaseComObject(wb);
Marshal.ReleaseComObject(xlApp);