Translating C# to X#

[Kees Bouw]

There are a lot of C# code examples on the internet and sometimes I have trouble translating them, in the most efficient way, to X#. For example this piece of code:

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// Draw the custom border to appear 3-dimensional.
e.Graphics.DrawLines(SystemPens.ControlLightLight, new Point[] {
    new Point (0, e.Bounds.Height - 1), 
    new Point (0, 0), 
    new Point (e.Bounds.Width - 1, 0)
});

What would be the best X# equivalent?
(The code is on this page: https://learn.microsoft.com/en-us/dotne ... esktop-9.0)
Thanks in advance

[Chris]

Hi Kees,

The 2nd parameter is a (fixed size) array (of Point(s)), given it's elements on definition. For an INT array, the X# syntax to do this would be

aArrayOfInts := <INT> {1,2,3,6,7,0}

For an array of point, you need to instantiate Point objects withing the definition. It helps to divide this in two lines, by using an intermediate variable, to make it easier to read:

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LOCAL aPoints AS Point[] // single dim fixed size array of Point
aPoints := <Point> { Point {0, e:Bounds.Height - 1}, Point {0, 0}, Point {e:Bounds.Width - 1, 0} } // specify all the array elements at once

e:Graphics:DrawLines(SystemPens.ControlLightLight, aPoints)

[Kees Bouw]

Hi Chris,

Thank you very much!

aArrayOfInts := <INT> {1,2,3,6,7,0}

Would this be the same as:

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aArrayOfInts := ARRAY OF INT
aArrayOfInts := {1,2,3,6,7,0}

Or does the < > make it into something special? It looks like some sort of cast.

---

LOCAL aPoints AS Point[] // single dim fixed size array of Point

Would this be the same as:

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aPoints := ARRAY OF Point

Or is for example Point[] a dotnet array and an ARRAY OF Point an X# array?

---

aPoints := <Point> { Point {0, e:Bounds.Height - 1}, Point {0, 0}, Point {e:Bounds.Width - 1, 0} } // specify all the array elements at once

It does work but I don't really understand the <> {} syntax. I also can't find it in the Help. Do you know where this is explained a little more?

Different topic: the horizontal line that you can add in this editor is hardly visible, it is grey on grey.

Thanks!

Kees.

[robert]

Kees,

ARRAY OF INT is not the same as INT[]
ARRAY OF INT produces a dynamic array, just like the arrays in VO, but its elements are of type INT and not of type USUAL.

Robert

[Chris]

Hi Kees,

The <> syntax was introduced by Don in vulcan, so we used it also in X# for compatibility. I think the logic behind it was to use a similar pattern to the syntax used universally for generics, where you specify the generic type like this List<INT> or Dictionary<STRING,Point>.

If you don't like this, in X# you can also use this syntax:

aPoints := Point[] {3} { Point {0, e:Bounds.Height - 1}, Point {0, 0}, Point {e:Bounds.Width - 1, 0} }

The first {3} is used to denote the size of the array, rest of the line lists the array elements. "Point[]" is the universal way in .Net for specifying fixed size arrays.