You can use a library called ExcelLibrary. It's a free, open source library posted on Google Code:
ExcelLibrary
This looks to be a port of the PHP ExcelWriter that you mentioned above. It will not write to the new .xlsx format yet, but they are working on adding that functionality in.
It's very simple, small and easy to use. Plus it has a DataSetHelper that lets you use DataSets and DataTables to easily work with Excel data.
ExcelLibrary seems to still only work for the older Excel format (.xls files), but may be adding support in the future for newer 2007/2010 formats.
You can also use EPPlus, which works only for Excel 2007/2010 format files (.xlsx files). There's also NPOI which works with both.
There are a few known bugs with each library as noted in the comments. In all, EPPlus seems to be the best choice as time goes on. It seems to be more actively updated and documented as well.
Also, as noted by @АртёмЦарионов below, EPPlus has support for Pivot Tables and ExcelLibrary may have some support (Pivot table issue in ExcelLibrary)
Here are a couple links for quick reference:
ExcelLibrary - GNU Lesser GPL
EPPlus - GNU (LGPL) - No longer maintained
EPPlus 5 - Polyform Noncommercial - Starting May 2020
NPOI - Apache License
Here some example code for ExcelLibrary:
Here is an example taking data from a database and creating a workbook from it. Note that the ExcelLibrary code is the single line at the bottom:
//Create the data set and table
DataSet ds = new DataSet("New_DataSet");
DataTable dt = new DataTable("New_DataTable");
//Set the locale for each
ds.Locale = System.Threading.Thread.CurrentThread.CurrentCulture;
dt.Locale = System.Threading.Thread.CurrentThread.CurrentCulture;
//Open a DB connection (in this example with OleDB)
OleDbConnection con = new OleDbConnection(dbConnectionString);
con.Open();
//Create a query and fill the data table with the data from the DB
string sql = "SELECT Whatever FROM MyDBTable;";
OleDbCommand cmd = new OleDbCommand(sql, con);
OleDbDataAdapter adptr = new OleDbDataAdapter();
adptr.SelectCommand = cmd;
adptr.Fill(dt);
con.Close();
//Add the table to the data set
ds.Tables.Add(dt);
//Here's the easy part. Create the Excel worksheet from the data set
ExcelLibrary.DataSetHelper.CreateWorkbook("MyExcelFile.xls", ds);
Creating the Excel file is as easy as that. You can also manually create Excel files, but the above functionality is what really impressed me.
You have at least three options. I have presented them in order of usage preference.
Method 1 - You can use the SC tool (Sc.exe) included in the Resource Kit.
(included with Windows 7/8)
Open a Command Prompt and enter
sc delete <service-name>
Tool help snippet follows:
DESCRIPTION:
SC is a command line program used for communicating with the
NT Service Controller and services.
delete----------Deletes a service (from the registry).
Method 2 - use delserv
Download and use delserv command line utility. This is a legacy tool developed for Windows 2000. In current Window XP boxes this was superseded by sc described in method 1.
Method 3 - manually delete registry entries (Note that this backfires in Windows 7/8)
Windows services are registered under the following registry key.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
Search for the sub-key with the service name under referred key and delete it. (and you might need to restart to remove completely the service from the Services list)
Best Answer
The ability of applications to block a pending system shutdown was severely restricted in Windows Vista. The details are summarized in two handy articles on MSDN: Shutdown Changes for Windows Vista and Application Shutdown Changes in Windows Vista.
As that page indicates, you shouldn't rely on the ability to block shutdown for any longer than 5 seconds. If you wish to attempt to block a pending shutdown event, your application should use the new
ShutdownBlockReasonCreate
function, which allows you to register a string that explains to the user the reason why you think the shutdown should be blocked. The user reserves the ability to heed your advice and cancel the shutdown, or throw caution to the wind and cancel anyway.As soon as your application finishes doing whatever it is that should not be interrupted by a shutdown, you should call the corresponding
ShutdownBlockReasonDestroy
function, which frees the reason string and indicates that the system can now be shut down.Also remember that Windows Services now run in an isolated session and are prohibited from interacting with the user. My answer here also provides more details, as well as a pretty diagram.
Basically, this is impossible. Windows is going to fight you tooth and nail over starting up a separate process from your Service, as well as any attempt you make to block a pending shutdown. Ultimately, the user has the power to override anything you try to pull. This sounds like something you should solve using security policies, rather than an application—ask questions about that on Server Fault.