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export dynamic html table to excel

i am generating dynamic html table using web browser control . And now, im having problem to export it to excel. As im searching it thru internet, mostly said use syntax"Response.write" or "htmlcontext.current" but i cannot use those syntax due to I'm using Windows Form.
is there any other way to export it to excel? I really need help on this. Thanks!

There are several tools available to generate Excel documents from .Net, for example:
SpreadSheetLight
NPOI
EPPlus
ClosedXML

Which is the best way to manipulate data/sheet of an excel document in C#

I'm currently busy with a task that involves both manipulating data in an excising excel document as well as the sheet itself.
In the past I've always used OleDbConnection and OleDbCommand to work with excel, but I've been reading about something called a Workbook and I'm not sure which way I should go about this.
Some examples of what I need to do include-
Inserting a new column
Deleting old columns
Setting a cell a certain colour depending on it's contents
Looking for duplicates and deleting them.
In your option which way would be the most efficient way to go about this.
Thanks

Best way would be to go with excel interop if you don't want to use any third party library.
Interop works and any action can be performed which you have mentioned in your question.
Refer this link for more info: http://csharp.net-informations.com/excel/csharp-excel-tutorial.htm
PS: above link is for c# and for interop to work ms excel must be installed on the system, this can be implemented in vb.net as well.
Hope this helps.

I have used Visual Studio Tools for Office, you will have workbooks, worksheets, columns, ranges, etc. Easy to manipulate using C#.
https://msdn.microsoft.com/en-us/library/bb608603.aspx

Install this package into your project Further no need to install Excel also this is fast mothod https://www.nuget.org/packages/ExcelDataReader/

Is it possible to programatically convert a Cell Range in Excel to HTML

I don't mind using any external libraries in order to achieve this. I need to get the HTML representation of a Cell Range in Excel (including all formatting such as borders, font style, etc) inside my C# application. We're trying to automate a process where the user copies certain ranges from some excel files to another system.
I've tried using NPOI, COM Interop, OpenXML, and it seems there are no built-in ways to export just a smaller part of a workbook to HTML. NPOI does have a converter for old formats though, but it converts the entire file. And I could use a XLST transformation to convert the OpenXML representation to HTML. But it would take a lot of time which I don't exactly have right now.
Am I missing something? How does Excel itself save its files to HTML format? Can I use this to my advantage somehow? Are there any libraries out there able to do this?
I've done a lot of research but found nothing.

Need to automate crunching of excel data?

I have processes running on Windows XP/7. They generate weekly .csv data files. I have a bunch of excel formulas that crunch the numbers for each .csv file produced for the week separately and then when adding the weekly data to the one big spreadsheet containing all the data put together.
The number of rows varies each week and for each process. So I can't hardcode that number in my dozens of formulas. So right now I go through this stupid process of manually entering the formulas each week into the .csv files.
There's got to be a way of automating this. Just now I quickly looked into doing this through C# or VB code. Could somebody recommend the best way to do this. Is C# or VB the right way to go? If so, any hints on how to put it all together - what's the model to use? For example, would it look something like this:
C# module reads in .csv data file
C# module creates an Excel spreadsheet and populates it with the .csv data
C# module runs my formulas on the all the rows.
Is that how one would approach it? Is there a better way for somebody who has very limited knowledge of C# or VB? I know Java and C++.
Any advice would be highly appreciated.
Thanks

From your explanations in comments, it appears that having a series of template Excel sheets would greatly facilitate the task.
So, for each process that generates data, you say the formulas are always the same, meaning that the columns are always the same (am I right?).
So, even if you don't know how many rows of data, you can still either create a template where only the first row is filled with formulas, and then you simply copy that row over and over, filling it with data as needed, or, you could fill a relatively "comfortable" number of rows with those same formulas, and fill in the data.
There are tons of atricles on how to Interop with Excel, so it's beyond my intent to provide you with specific code, but the idea is good.
If I can allow myself, I have worked in the past with a very interesting tool call Flexcel Studio for .NET, and I have found it to be of great help when it came to generating Excel sheets based on such templates.
Cheers

As others have suggested, I would recommend performing the calculations outside of excel if possible. There are plenty of stats libraries out there that are friendlier to work with than going through the hassle of moving data into excel, applying formulas to cell ranges, and so on.
If you really want to go the excel route, you can either use open-source libraries such as EPPLUS (.NET) or POI (Java) to work with .XLSX files directly. Some libraries do not support function evaluation so you will need to consider this when deciding on a library to use.
If you go with COM interop, you should read about about the following: Considerations for server-side Automation of Office.
As for the C# or VB (if not java with POI), I would go with C#. C# syntax is similar to java.

There might be a really simple solution to this problem.
Add 1 piece of auxiliary data to the .csv file either programmatically when running my process or when creating the .xlsx file (with all the formulas) from the .csv file. The auxiliary piece of data is the row count which will be in some known location.
Then modify all my formulas to use the INDIRECT function to specify the range using the cell
with the auxiliary piece of data.
I think that might work.

c# read excel worksheet

Could someone help me read a simple excel worksheet in c# app? I'd like to be able to iterate each row and have a handle on each of the columns.
Thanks,
rod.

This one is the easiest method I have found:
Create Excel (.XLS and .XLSX) file from C#

The general method is to use Excel COM Interop. A quick google will find plenty of tutorials. Here's one for creating a sheet - it should point you in the direction (reading is pretty much the same).
An alternative method is to use ADO.Net. This is only really viable if your Excel sheet is well formed as a table ( ie. Database), but is easier than the interop approach.

Here is a sample using OLEDB
http://www.techiesweb.net/2009/12/reading-records-excel-file-insert-database-aspnet/

If you are going to open Excel 2007 or 2010 workbook (ooxml format), you can download Open XML SDK 2.0 for Microsoft Office (which doesn't require you to have MS office installed).

While Excel COM Interop works, it requires Excel to be installed on the client machine. If that isn't an issue then all good, but if it is you might consider looking at the Aspose.Cells library (no affiliation, just used them before). They're simple and powerful, although do carry a commercial license cost.

I've used ADO.NET and Jet in the past. Be warned that if you have columns that aren't obviously of one type you will see weird things happen. Jet tries to assign a datatype to a column based on the first several vales. The nice thing is that you can query the spreadsheet like it is a table.