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C# 7.0 improves the expression body feature
C# 6.0 already improved the expession body feature. With this improvement, a read-only property like this :
public string ExampleText
{
get { return "this is my text"; }
}
can be rewritten in a shorter way :
public string ExampleText => "this is my text";
As you can see, with C# 6 th property is more compact, more clear. There is no more brackets, or return keyword anymore; even the get accessor disappeared.
Personally, I use very often the C# 6 syntactic sugar, so I was happy to see that this feature was extended to constructors, destructors and setters.
Expression-Bodied Constructors
If you have a constructor who doesn't need complex implementation, you can now reduce him to only one line.
C# 6
private bool Initialized = false;
public MyClass()
{
Initialized = true;
}
private bool Initialized = false;
public MyClass() => Initialized = true;
Expression-Bodied Destructors
The same is true for destructors :
C# 6
public ~MyClass()
{
Console.WriteLine($"{nameof(MyClass)}'s destructor called");
}
public ~MyClass() => Console.WriteLine($"{nameof(MyClass)}'s destructor called");
Expression-Bodied Property Accessors
This feature was available with C# 6 but only for read-only properties, but with C# 7, you can now write your setters in the same compact way than the getters.
The next example is a simple case to see what the syntax is, but in the real-life you could be more simple that this using an auto property who will reduces the code more, but let's see how you can implement a very simple property with the C# 7 improvement :
C# 6
private string _exampleText;
public string ExampleText
{
get { return _exampleText; }
set { _exampleText = value; }
}
private string _exampleText;
public string ExampleText
{
get => _exampleText;
set => _exampleText = value;
}
Summary
It's clear that Microsoft wants to continue with productivity enhancements for the next version of C#, such a good thing. The less words you have in your code, the less time you spend to write, read and understand it.
To keep you inform about the evolution of C#, you can read the design notes discussed on GitHub, such interesting.