The purpose of the using declaration in C# 8.0 is to simplify the syntax for ensuring the disposal of disposable resources (types that implement the IDisposable interface).
It introduces a more concise and readable way to manage the lifetime of such resources compared to the traditional using statement.
Traditional using Statement (C# 1.0 and later):
using (Font font = new Font("Arial", 10.0f))
{
// Use the font object here
Console.WriteLine($"Font Family: {font.FontFamily.Name}, Size: {font.Size}");
}
// font.Dispose() is automatically called when the block ends
using Declaration (C# 8.0):
using Font font = new Font("Arial", 10.0f);
// Use the font object here
Console.WriteLine($"Font Family: {font.FontFamily.Name}, Size: {font.Size}");
// font.Dispose() is automatically called when the enclosing scope ends
The scope of the using declaration extends to the entire enclosing scope in which it is declared. This enclosing scope can be:
- The body of a method:
- A local block within a method:
- The scope of a static local function (introduced in C# 8.0 as well):