C# Forms Collection in Class

I need to pass collections to a form from a class.  I created a public method in the form.  I was going to write the following code
FormsCollection fc = Application.OpenForms;

foreach (var f in fc)
{ 
  if (f.GetType() == typeof(MyForm)f;
      form.CallMyMethod;
  }
}

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I ether need to do that or I need to open a form from a class.

But it seems like I can't do that in a class.  Any other ideas?
LVL 1
CipherISAsked:
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Éric MoreauConnect With a Mentor Senior .Net ConsultantCommented:
I just found some time to provide a sample using an interface.

First create an interface:
namespace WindowsFormsApplication1
{
    interface IMyInterface1
    {
        void DoSomething();
    }
}

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Then create your class:
using System.Linq;

namespace WindowsFormsApplication1
{
    public static class Class1
    {
        public static void DoSomethingGeneric()
        {
            System.Windows.Forms.Application.OpenForms
           .OfType<IMyInterface1>()
           .ToList()
           .ForEach(form => form.DoSomething());
        }
    }
}

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And finally your form:
using System;
using System.Windows.Forms;

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form, IMyInterface1
    {
        public Form1()
        {
            InitializeComponent();
        }

        public void DoSomething()
        {
            MessageBox.Show("Interface implementation!");
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Class1.DoSomethingGeneric();
        }
    }
}

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0
 
Guy Hengel [angelIII / a3]Connect With a Mentor Billing EngineerCommented:
I think you only are missing 1 small detail:

FormsCollection fc = Application.OpenForms;

foreach (var f in fc)
{ 
  if (f.GetType() == typeof(MyForm)f;
     MyForm mf = (MyForm)f;
     mf.CallMyMethod;
  }
}

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0
 
CipherISAuthor Commented:
When I type FormsCollection it doesn't like that in the class
0
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Éric MoreauConnect With a Mentor Senior .Net ConsultantCommented:
you need to add a using clause for System.Windows.Forms (and probably a reference to it as well)
0
 
Fernando SotoConnect With a Mentor RetiredCommented:
You will need a using statement for System.Windows.Forms and add reference to System.Windows.Forms.dll if it is in a different project that already does not have that reference
0
 
käµfm³d 👽Connect With a Mentor Commented:
Why not just?

Application.OpenForms
           .OfType<MyForm>()
           .ToList()
           .ForEach(form => form.CallMyMethod());

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0
 
CipherISAuthor Commented:
Ok, adding the reference to Windows.Forms helped but now when I add the name of my form it won't find it as I need to add a reference to it.  My class is in another project and I can't add the project that my form is in because it would create a circular reference.

Any ideas?
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Éric MoreauConnect With a Mentor Senior .Net ConsultantCommented:
can you create an interface? or should you use Reflection (but then you loose all intellisense and compilation errors)?
0
 
CipherISAuthor Commented:
Unsure how to create an interface to get it to work now.  What I did was call my method and pass my objects with reference.

Excuse the rude code.
MyObject o = new MyObject();

o.MyMethod(ref ClassObject);

MyObject.MyMethod(ref ClassObject classObject)

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The problem that I'm having is that the changes in my method are not pushing back up.
0
 
Éric MoreauSenior .Net ConsultantCommented:
>>The problem that I'm having is that the changes in my method are not pushing back up.

What? Have you done a full rebuild? Are your 2 projects in the same solution?

For the interfaces, check https://msdn.microsoft.com/en-us/library/ms173156.aspx
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CipherISAuthor Commented:
They are in the same solution
0
 
CipherISAuthor Commented:
I don't understand how the interface would help me.  Why isn't the ref passing the values back?
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Éric MoreauSenior .Net ConsultantCommented:
an interface would avoid circular reference yet letting use early binding.

but before going further, are you sure your architecture is good? Why a class which in theory knows nothing about the forms should call a method in it?
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CipherISAuthor Commented:
I need to get better with interfaces.  Unfortunately, I don't have time to rewrite it.  I was able to get the ref to work.  

I'm curious how to implement the interface to get this to work as you are thinking.
0
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