Why to use “using” in C#?

The reason for the using statement is to ensure that the object is disposed as soon as it goes out of scope, and it doesn't require explicit code to ensure that this happens.
Microsoft documentation states that using has a double function, both as a directive and in statements. As a statement, as it was pointed out here in other answers, the keyword is basically syntactic sugar to determine a scope to dispose an IDisposable object. As a directive, it is routinely used to import namespaces and types. Also as a directive, you can create aliases for namespaces and types.

using System.IO; // using 'using' here

class UsingStatement
{
    static void Main()
    {
        var buffer = new char[50];
        using (StreamReader streamReader = new("file1.txt")) // using 'using' here
        {
            int charsRead = 0;
            while (streamReader.Peek() != -1)
            {
                charsRead = streamReader.Read(buffer, 0, buffer.Length);
                //
                // Process characters read.
                //
            }
        }
    }
}

3 Replies

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Brahma Prakash Shukla3y ago
Accepted answer
“Using” statement calls – “dispose” method internally, whenever any exception occurred in any method call and in “Using” statement objects are read only and cannot be reassignable or modifiable.
+5
Rajanikant Hawaldar3y ago
The reason for the using statement is to ensure that the object is disposed as soon as it goes out of scope, and it doesn't require explicit code to ensure that this happens.
Microsoft documentation states that using has a double function, both as a directive and in statements. As a statement, as it was pointed out here in other answers, the keyword is basically syntactic sugar to determine a scope to dispose an IDisposable object. As a directive, it is routinely used to import namespaces and types. Also as a directive, you can create aliases for namespaces and types.
```
using System.IO; // using 'using' here

class UsingStatement
{
    static void Main()
    {
        var buffer = new char[50];
        using (StreamReader streamReader = new("file1.txt")) // using 'using' here
        {
            int charsRead = 0;
            while (streamReader.Peek() != -1)
            {
                charsRead = streamReader.Read(buffer, 0, buffer.Length);
                //
                // Process characters read.
                //
            }
        }
    }
}
```
+4
Naresh Beniwal3y ago
https://www.c-sharpcorner.com/UploadFile/ff0d0f/using-keyword-in-C-Sharp/
+3