VB.NET := の意味
:= (コロンイコール)は名前付き引数指定
Public Function SampleMethod1(Optional x As Integer = 0, Optional y As Integer = 0, Optional z As Integer = 0) As Integer Return x + y * 2 + z * 3 End Function WriteLine($"SampleMethod1(x:=1,y:=2,z:=3)={SampleMethod1(x:=1, y:=2, z:=3)}")