CSharp and Excel

[gumbystation]

I am looking to take data from an excel spreadsheet into a csharp
application to manipulate the data in various ways. Currently, I am
using VS2005 (self-taught C#) and Excel 2000. I have researched into
using the Excel.Application object and have successfully openned a
worksheet in Excel (though hidden from the user).

The problem now comes when trying to get the data off of a spreadsheet.
When I try to create an instance of the worksheet, it fails:

oXL.Sheets["Sheet1"].Activate();

And even if I get that to work, I don't know how to pull the data off
of the spread sheet. I understand that I will need to get the range,
which I can do. Anyways, here is what I have so far:

oXL = new Excel.Application();
oWB = (Excel._Workbook)(oXL.Workbooks.Open(@"C:\workbook.xls",
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing));
oXL.Sheets("Sheet1").Activate(); //Doesn't compile
Excel.Worksheets tmpWBs = oXL.Sheets;
Excel.Worksheet tmpWB = tmpWBs["Sheet1"];
tmpWB.Activate();
stringTemp = (string)tmpWB.Cells[1,1];
// Rest of code

Any help is greatly appreciated.

 

[RobinS]

First, you need to get to the Worksheet object through
the Workbook object, not through the Application object.

Second, you need to cast it to an ExcelWorksheet type
in order to activate it.

This is how to do it in VB2005. (Yes, I know it's a C# ng,
please don't castigate me -- isn't VB better than nothing?)

xlApp is my Excel.Application object.
FinalWkBk is the index into the workbooks collection, and
I'm using WorkSheets(1) (it's the first one in the workbook;
this is not 0-based).

Dim xlTwo As Excel.Worksheet = _
CType(xlApp.Workbooks(FinalWkBk).WorkSheets(1), Excel.WorkSheet)
xlTwo.Activate()

I think that translates to this, but I'm posting the VB code in
case I'm wrong, so everybody can correct me.

Excel.Worksheet xlTwo = _
Excel.Worksheet(xlApp.Workbooks(FinalWkBk).WorkSheets(1))
xlTwo.Activate()

So for you, this would probably be

oXL = new Excel.Application()
oWB = (Excel._Workbook)(...blahblahblah)

Excel.Worksheet oSheet = _
Excel.Worksheet(oWB.WorkSheets("Sheet1"))
oSheet.Activate()


Good luck.
Robin S.

 

[Frank Rizzo]

My comment won't solve your problem, however, i just want to pass on the
some wisdom having dealt with Office and other interop.

If you want to communicate with legacy COM objects, such as Office or
DAO or RDO, do yourself a favor and use VB2005. Office objects have a
ton of optional parameters (as your code snippet illustrates) in pretty
much every single method call. So unless, you want to waste your time
making sure that you passed in enough Type.Missing statements, just use
VB2005's ability to use optional parameters.

Regards

 

[Mark Rae]

oXL.Sheets("Sheet1").Activate(); //Doesn't compile

oXL.Sheets["Sheet1"].Activate();

 

[Luke Smith]

I agree. Having done Excel programming from c# before I wish I would have
started the project in VB.NET.

There is a managed library (it costs but depending on the size of the
project could save you time and money) for doing spreadsheet work
(http://www.aspose.com/).

Another thing to note is if you are wanting to do Office interop from an
ASP.NET website don't bother, office isn't designed to support it (altho it
is possible). Go for the aspose approach above.

Luke
http://blog.lukesmith.net

My comment won't solve your problem, however, i just want to pass on the
some wisdom having dealt with Office and other interop.

If you want to communicate with legacy COM objects, such as Office or DAO
or RDO, do yourself a favor and use VB2005. Office objects have a ton of
optional parameters (as your code snippet illustrates) in pretty much
every single method call. So unless, you want to waste your time making
sure that you passed in enough Type.Missing statements, just use VB2005's
ability to use optional parameters.

Regards

I am looking to take data from an excel spreadsheet into a csharp
application to manipulate the data in various ways. Currently, I am
using VS2005 (self-taught C#) and Excel 2000. I have researched into
using the Excel.Application object and have successfully openned a
worksheet in Excel (though hidden from the user).

The problem now comes when trying to get the data off of a spreadsheet.
When I try to create an instance of the worksheet, it fails:

oXL.Sheets["Sheet1"].Activate();

And even if I get that to work, I don't know how to pull the data off
of the spread sheet. I understand that I will need to get the range,
which I can do. Anyways, here is what I have so far:

oXL = new Excel.Application();
oWB = (Excel._Workbook)(oXL.Workbooks.Open(@"C:\workbook.xls",
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing));
oXL.Sheets("Sheet1").Activate(); //Doesn't compile
Excel.Worksheets tmpWBs = oXL.Sheets;
Excel.Worksheet tmpWB = tmpWBs["Sheet1"];
tmpWB.Activate();
stringTemp = (string)tmpWB.Cells[1,1];
// Rest of code

Any help is greatly appreciated.

 

[gumbystation]

@ Robin:
I'll give that a try and let you know how it goes. Plus I'll start
working on the VB code too (see comment in @ Frank)

@ Frank:
My initial goal is to create the same application in C# and VB just to
gain the experience in both. So even if I do create the VB app, I will
have only delayed my progress with C#. And I know that C# is more
picky about parameters but I figure that if I use C# first, I'll
understand the functions better than if I use VB first. I will be
using VB at some time though. Would you suggest doing both
applications parallel to each other such that I can test out with VB if
C# doesn't work?

@ Mark:
I had updated it that problem in another version of the code that isn't
readily accessible at the moment. Even that code didn't compile:

oXL.Sheets["Sheet1"].Activate();

@ Luke:
While that product looks really great, I do not think I will use it as
this is simply a hobby project and not for an actual company, and being
a college student... well hope you understand. This is simply a
windows app and not a website, if I do that, I probably would interact
with Google's spreadsheet instead. Thanks for the tips

I agree. Having done Excel programming from c# before I wish I would have
started the project in VB.NET.

There is a managed library (it costs but depending on the size of the
project could save you time and money) for doing spreadsheet work
(http://www.aspose.com/).

Another thing to note is if you are wanting to do Office interop from an
ASP.NET website don't bother, office isn't designed to support it (altho it
is possible). Go for the aspose approach above.

Lukehttp://blog.lukesmith.net

My comment won't solve your problem, however, i just want to pass on the
some wisdom having dealt with Office and other interop.

If you want to communicate with legacy COM objects, such as Office or DAO
or RDO, do yourself a favor and use VB2005. Office objects have a ton of
optional parameters (as your code snippet illustrates) in pretty much
every single method call. So unless, you want to waste your time making
sure that you passed in enough Type.Missing statements, just use VB2005's
ability to use optional parameters.

Regards

I am looking to take data from an excel spreadsheet into a csharp
application to manipulate the data in various ways. Currently, I am
using VS2005 (self-taught C#) and Excel 2000. I have researched into
using the Excel.Application object and have successfully openned a
worksheet in Excel (though hidden from the user).
The problem now comes when trying to get the data off of a spreadsheet.
When I try to create an instance of the worksheet, it fails:
oXL.Sheets["Sheet1"].Activate();
And even if I get that to work, I don't know how to pull the data off
of the spread sheet. I understand that I will need to get the range,
which I can do. Anyways, here is what I have so far:
oXL = new Excel.Application();
oWB = (Excel._Workbook)(oXL.Workbooks.Open(@"C:\workbook.xls",
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing, Type.Missing,
Type.Missing, Type.Missing, Type.Missing,
Type.Missing));
oXL.Sheets("Sheet1").Activate(); //Doesn't compile
Excel.Worksheets tmpWBs = oXL.Sheets;
Excel.Worksheet tmpWB = tmpWBs["Sheet1"];
tmpWB.Activate();
stringTemp = (string)tmpWB.Cells[1,1];
// Rest of code
Any help is greatly appreciated.- Hide quoted text -- Show quoted text -

 

[Laurent Bugnion [ASP.NET MVP]]

Hi,

I am looking to take data from an excel spreadsheet into a csharp
application to manipulate the data in various ways. Currently, I am
using VS2005 (self-taught C#) and Excel 2000. I have researched into
using the Excel.Application object and have successfully openned a
worksheet in Excel (though hidden from the user).

Just want to point that you can also access Excel using ADO.NET. If your
application does nothing but read data, my guess is that the code would
be easier. Additionally, you don't need to have Excel installed on the
target machine, only ADO.NET.

See this:
http://geekswithblogs.net/lbugnion/archive/2006/08/25/89315.aspx

HTH,
Laurent