excel-interop

I have the following C# function in my project, which is supposed to open and return an existing Excel workbook object: Application _excelApp; // ... private Workbook OpenXL(string path, string filename) { try { if (_excelApp == null) { _excelApp = new Application(); } Workbook workBook = _excelApp.Workbooks.Open(path + filename, // Name 0, // Do not update links true); // Open read-only return workBook; } catch (Exception e) { _excelApp = null; throw new ArgumentException("Error opening " + path + filename, e); } } But when I run it with "C:\" and "scratch.xlsx", the Open() call throws the

I am converting several VBA projects to Windows form applications. The only problem I have is that some of the functionality of Excel is essential to the application, such as R1C1 formulas. I do not want to instantiate the Excel application or access saved worksheets. All of the data is retrieved by querying Oracle databases. 2-Dimensional arrays are not an option because the columns contain differing datatypes, and DataGridViews are too slow to work with. I thought simply dimming a Microsoft.Office.Interop.Excel.Worksheet object would be enough, but the program kept failing and upon

Error: Cannot convert type 'string' to 'object[*,*]' That's the error I have been getting. Can someone give me some pointers so that I can avoid it? Thanks. Note: Interestingly, (object[,])range.get_Value(XL.XlRangeValueDataType.xlRangeValueDefault) will only produce this bug when range.Count == 1 . It works fine when count is equal to and above 2. sample code: object[,] arrValue; //global variable private string[] createFormulaCollection() { ArrayList s = new ArrayList(); try { //look at the currently active excel sheet //iterate through cells (not Null) and find the one contains IES(...) /

Is it possible to determine whether Excel is running in 32-bit or 64-bit from the Microsoft.Office.Interop.Excel.ApplicationClass? Edit The solution should work for both Excel 2010 and Excel 2007 This code should give you the "bitness" of Excel. Microsoft.Office.Interop.Excel.ApplicationClass app = new Microsoft.Office.Interop.Excel.ApplicationClass(); if (System.Runtime.InteropServices.Marshal.SizeOf(app.HinstancePtr) == 8) { // excel 64-bit } else { // excel 32-bit } EDIT: here is another version that should work for previous versions of Excel as well. Just pass an ApplicationClass reference

Using VSTO or some related technology, is it possible to programmatically embed a button in a cell of an Excel worksheet, and configure it to call a C# function when it is clicked? How? Thanks. With a VSTO document customization (i.e., a Workbook with .Net code attached), you can add and remove controls at runtime to the Worksheets of the project. The following code illustrates the idea: public partial class Sheet1 { private void Sheet1_Startup(object sender, System.EventArgs e) { var button = this.Controls.AddButton(10, 10, 50, 50, "My Button"); button.Text = "My Button"; button.Click += new

I am in the process of writing an application in C# which will open an Excel spreadsheet (2007, for now) via interop, do some magic, then close. The "magic" part is non-trivial, so this application will contain many references to many COM objects spawned by Excel. I have written this kind of application before (too many times, in fact) but I've never found a comfortable, "good smell" approach to interacting with COM objects. The problem is partly that, despite significant study, I still don't perfectly understand COM and partly that the interop wrappers hide much that probably shouldn't be