best way to store data in wpf application

i just want to know about the best way to store sensitive and secured data in wpf application tha开发者_如何学JAVAt will not appear inside the exe file like databases and will store data and retrieve it when program start up again

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Going by the latest comment, it seems that you need to encrypt user input data. Depending on the size of the data you could go with SQL Server 2008 R2 Express or SQL Server Compact. You can have a look at SQL Server 2008 R2 CE encryption or SQL Server 2008 R2 Express encryption.

If you are not looking at databases, then you could have a look at file based encryption using the System.Security.Cryptography namespace.

Higher levels of security are available in the enterprise version of SQL Server. More information on encryption levels in SQL Server 2008 can be found here.

Note that encryption of the database (depending on the algorithm used) can negatively affect the performance.