Reading from Excel (Range into multidimensional Array) C#

You can read the value of Range as array:

using (MSExcel.Application app = MSExcel.Application.CreateApplication()) 
{
    MSExcel.Workbook book1 = app.Workbooks.Open( this.txtOpen_FilePath.Text);
    MSExcel.Worksheet sheet = (MSExcel.Worksheet)book1.Worksheets[1];
    MSExcel.Range range = sheet.GetRange("A1", "F13");

    object value = range.Value; //the value is boxed two-dimensional array
}

This code snippet is from .NET wrapper for MS Office. But same princip is in VSTO or VBA in MS Excel.

Here is the C# code to do this with SpreadsheetGear:

    // Load the workbook.
    SpreadsheetGear.IWorkbook workbook = SpreadsheetGear.Factory.GetWorkbook(@"MyWorkbook.xlsx");
    // Get a range of cells as an array of object[,].
    object[,] values = (object[,])workbook.Worksheets["MySheet"].Cells["A1:J10"].Value;

SpreadsheetGear also provides fast APIs for accessing cells one at a time so that you can avoid copying the values to an array without sacrificing performance.

Disclaimer: I own SpreadsheetGear LLC