is FileStream necessary?

[John Salerno]

In Murach's C#, it shows that StreamWriter and StreamReader both take a
stream object as a parameter, and the book's examples of these two
classes all first create a FileStream object. But I notice in the VS
help files that they use the two classes directly, without creating a
stream, and that StreamWriter and StreamReader can both take a string
parameter as well. Is this new to .NET 2.0? What's the difference
between doing this and explicitly creating a FileStream object? Is it
called implicitly anyway?

 

[Truong Hong Thi]

They are just about the same. If you pass a file path instead of a
stream, .NET will internally create a FileStream for that file.

 

[Jon Skeet [C# MVP]]

In Murach's C#, it shows that StreamWriter and StreamReader both take a
stream object as a parameter, and the book's examples of these two
classes all first create a FileStream object. But I notice in the VS
help files that they use the two classes directly, without creating a
stream, and that StreamWriter and StreamReader can both take a string
parameter as well. Is this new to .NET 2.0? What's the difference
between doing this and explicitly creating a FileStream object? Is it
called implicitly anyway?

Yes, a FileStream is created anyway. The difference is that by creating
the FileStream yourself, you can specify different file modes, share
access etc.

Jon

 

[William Stacey [MVP]]

It is a bit confusing at first I agree. Also, things like the static
File.Open() method also return a StreamReader with also wraps a FileStream.
IIRC, all file operations eventually have a FileStream as the base stream.

 

[John Salerno]

In Murach's C#, it shows that StreamWriter and StreamReader both take a
stream object as a parameter, and the book's examples of these two
classes all first create a FileStream object. But I notice in the VS
help files that they use the two classes directly, without creating a
stream, and that StreamWriter and StreamReader can both take a string
parameter as well. Is this new to .NET 2.0? What's the difference
between doing this and explicitly creating a FileStream object? Is it
called implicitly anyway?

Thanks guys!