How to add/remove Attribute from File (Bitwise Operation)

This article explains how to add or remove Attributes (Read-only, Hidden, etc.) from a file using Bitwise Operators.

Level: Beginner

Knowledge Required:
Bitwise Operations

Description:
In my previous post:

How to Make a Bit Zero in an Integer (Bitwise Operation)

I explained a technique through which we can make a bit Zero in an Integer. In which we used the XOR bitwise operator. XOR actually reverts the bit i.e. if 0 then makes it 1 and if 1 then makes it 0. Therefore we can use XOR to make the bit 0 (Zero) if we are sure that bit is NOT already zero, otherwise we should use the technique described in this post.

For example, we are going to remove the Read-only Attribute from a file.

Remove Read-only Attribute from File:

Dim f As System.IO.FileInfo
f = New System.IO.FileInfo("C:\ABC.txt")
f.Attributes = f.Attributes And (Not IO.FileAttributes.ReadOnly)

Therefore to make the bit zero from an integer we use code

MainIntVar = MainIntVar AND (NOT IntBitToRemove)

Above code is useful to remove the Attribute (Read-only, Hidden, etc.) from a file. Similarly we can add attributes to file,

Add Read-only Attribute to File:

Dim f As System.IO.FileInfo
f = New System.IO.FileInfo("C:\ABC.txt")
f.Attributes = f.Attributes Or  IO.FileAttributes.ReadOnly

See Also:
How to check a Bit whether it is 1 or 0 (zero) in an Integer (Bitwise Operations)
How to Make a Bit Zero in an Integer (Bitwise Operation)