A function to determine if the input filename is valid on Win32 platforms (that is, it does not include invalid characters, such as :\?...)

Write a set of bytes into a so-called binary file. The point is that we use BinaryWriter here and we have a byte array as input.

Set the read-only attribute of a file to true or false.

This is a function that receives a dataTable and return it in a pivoted way.

Simple loop through datatable

Second example of reading an excel file. Reading with a SELECT syntax.

First Example of reading an excel file. Just reading the file and loop throught 10 rows.

I will send the second example soon !!!

Example that shows how to populate a winforms combobox with csharp. It uses Data Access blocks (SqlHelper).

Prior to NETCF 2.0, this was a royal pain. Now, it's pretty straight-forward.

These three related functions provide basic Clipboard operations for text. While not terribly useful by themselves, they become more useful when attached to a field's context menu or, better yet, implemented in a custom control.

From RSA Security's website:
"RC4 is a stream cipher designed by Rivest for RSA Data Security (now RSA Security). It is a variable key-size stream cipher with byte-oriented operations. The algorithm is based on the use of a random permutation. Analysis shows that the period of the cipher is overwhelmingly likely to be greater than 10^100. Eight to sixteen machine operations are required per output byte, and the cipher can be expected to run very quickly in software. Independent analysts have scrutinized the algorithm and it is considered secure."

This implementation encodes the byte stream to be encrypted "in-place".

Example:
Byte[] Key = new Byte[5] { 12, 34, 22, 12, 32 };
Byte[] B = new Byte[10] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
// Examine B array before and after this next call.
RC4(ref B, Key);
// Examine B array before and after this next call.
RC4(ref B, Key);