Why should VB.NET file handling use a Using block?

A Using block ensures that a disposable resource is disposed when control leaves the block, including when an exception occurs. This makes file handles available for other operations and avoids cleanup code scattered across success and failure branches. It does not automatically handle every exception or guarantee that writing succeeded. Choose an encoding deliberately and use paths with appropriate permissions. The example reads a small file fully; for a large file, process lines incrementally instead of loading all text into memory.