Question

In C#, if I want to deterministically clean up non-managed resources, I can use the ‘using’ keyword. But for multiple dependent objects, this ends up nesting further and further:

using (FileStream fs = new FileStream('c:\file.txt', FileMode.Open)) {     using (BufferedStream bs = new BufferedStream(fs))     {         using (StreamReader sr = new StreamReader(bs))         {             // use sr, and have everything cleaned up when done.         }     } } 

In C++, I’m used to being able to use destructors to do it like this:

{         FileStream fs('c:\file.txt', FileMode.Open);     BufferedStream bs(fs);     StreamReader sr(bs);     // use sr, and have everything cleaned up when done. } 

Is there a better way in C# to do this? Or am I stuck with the multiple levels of nesting?

Answer 1

You don’t have to nest with multiple usings:

using (FileStream fs = new FileStream("c:\file.txt", FileMode.Open)) using (BufferedStream bs = new BufferedStream(fs)) using (StreamReader sr = new StreamReader(bs)) {     // all three get disposed when you're done } 

In .NET Core, there’s a new using statement which allows you to dispense with the parentheses, and the disposal happens at the end of the current scope:

void MyMethod() {     using var fs = new FileStream("c:\file.txt", FileMode.Open);     using var bs = new BufferedStream(fs);     using var sr = new StreamReader(bs);     // all three are disposed at the end of the method }