Constructor in Constructor

Question

is there some way how I can this do in C#? I can not use this(int,int) in C# code. Can you write me some similar code which will be in C# and will do the same things? Thank you! :)

public class JavaApplication2
{
    public static class SomeClass 
    {
        private int x;
        private int y;

        public SomeClass () { this(90,90); }
        public SomeClass(int x, int y) { this.x = x; this.y = y; }
        public void ShowMeValues ()
        {
            System.out.print(this.x);
            System.out.print(this.y);
        }
    }
    public static void main(String[] args) 
    {
        SomeClass myclass = new SomeClass ();
        myclass.ShowMeValues();
    }
}

if both constructors are public why not using just second one with parameters? Or if you want some default value for `int x` and `int y` - just set it in Class definition as `private int x = 90; ` — Fabio, Aug 23 '13 at 18:27
for example: http://stackoverflow.com/questions/3146152/c-if-a-class-has-two-constructors-what-is-the-best-way-for-these-constructors — shieldgenerator7, Aug 23 '13 at 18:28
possible duplicate of [call one constructor from another](http://stackoverflow.com/questions/4009013/call-one-constructor-from-another) — Rob Kennedy, Aug 23 '13 at 18:33

Reed Copsey · Answer 1 · 2013-08-23T18:32:50.353

4

Yes, C# can chain constructors:

public SomeClass() :this(90,90) {}
public SomeClass(int x, int y) { this.x = x; this.y = y; }

This is covered on MSDN in Using Constructors.

That being said, in C#, the class will have to not be static, as well.

edited Aug 23 '13 at 18:32

answered Aug 23 '13 at 18:25

Reed Copsey

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p.s.w.g · Accepted Answer · 2013-08-23T18:38:20.947

There are several things that need to be changed if you want to translate this to C#:

The main the problem is that you've declared SomeClass as static. It won't compile because static classes cannot have instance members. You need to remove the static keyword.
To invoke a constructor from another you need to use : this(...) after the constructor parameters (or : base(...) to invoke a constructor of the parent class).
Instead of System.out, for .NET applications you need to use System.Console.

This should work for you:

public class SomeClass 
{
    private int x;
    private int y;

    public SomeClass () : this(90,90) { }
    public SomeClass(int x, int y) { this.x = x; this.y = y; }
    public void ShowMeValues ()
    {
        Console.WriteLine(this.x);
        Console.WriteLine(this.y);
    }
}

Constructor in Constructor

2 Answers2