C# 4 and .NET 4

OC170 ❘ ChaPTer 53 c#, visuAl bAsic, c++/cli, And f#
// C#
public class Singleton
{
private static SomeData data = null;
public static SomeData GetData()
{
if (data == null)
{
data = new SomeData();
}
return data;
}
}
// use:
SomeData d = Singleton.GetData();
code snippet CSharp/Singleton.cs
// C++/CLI
public ref class Singleton
{
private:
static SomeData^ hData;
public:
static SomeData^ GetData()
{
if (hData == nullptr)
{
hData = gcnew SomeData();
}
return hData;
}
};
// use:
SomeData^ d = Singleton::GetData();
code snippet CPPCLI/Singleton.h
' Visual Basic
Public Class Singleton
Private Shared data As SomeData
Public Shared Function GetData() As SomeData
If data is Nothing Then
data = new SomeData()
End If
Return data
End Function
End Class
' Use:
Dim d as SomeData = Singleton.GetData()
code snippet VisualBasic/Singleton.fs
arrays
Arrays are discussed in Chapter 6, “Arrays and Tuples.” The Array class is always behind the scenes of
.NET arrays; declaring an array, the compiler creates a class that derives from the Array base class. When
C# was designed, the designers of the C# language took the bracket syntax for arrays from C++ and
extended it with array initializers:
// C#
int[] arr1 = new int[3] {1, 2, 3};
int[] arr2 = {1, 2, 3};
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