c# -- Pass data between MDI & child form

Nitin

Hi Guys,
I am new to c# so please bear with me. I am trying to write a small MDI application and I need help. Here is what I am trying to do.
I have few child forms in my application. Every child form have public function GetStr that returns the values of controls as a string & a button btnLoad.
I want to create a toolbar button on MDI form when user clicks it, it will get string from Active child form executing function GetStr. Also I want to create one more button when clicked, it will execute click action of btnLoad of the active child form. And this code should work for all forms.
I found few samples over the net but those are not working for me. I tried using "using" clause but it didnt work either because it returns value when form is initialized. I am using VS 2008, c#.
Any idea how do I achieve this most efficient way? Sample code is apprciated.

Thank you for you help in advance.

Nitin

4 Replies

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zirano latt17y ago
Accepted answer
Sorry Nitin. I didn't carefully read you question in my previous post. I read the title and thought that you want to share the data between MDI and child form.

Please see below code snippet. Hopefully, it is what you are asking about. Any doubt, please let me know.

public partial class MDIParentForm : Form
{
       //tool strip menu click event
        private void whoIsActiveToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (this.ActiveMdiChild != null)
            {
                IChildForm childForm = (IChildForm)this.ActiveMdiChild;
                MessageBox.Show(childForm.GetStr());
            }
        }
}

interface IChildForm
{
        string GetStr();
}

public partial class MDIChildForm1 : Form,IChildForm
{
        public string GetStr()
        {
            return "MDIChildForm1";
        }
}

public partial class MDIChildForm2: Form,IChildForm
{
        public string GetStr()
        {
            return "MDIChildForm2";
        }
}
Nitin17y ago
Great. Thank you so much. I appriciate your help.
Nitin17y ago
How do I execute click action of Button on MDIChildForm1 from MDI Toolbar when MDIChildForm1 is active?

Thank you so much. Appriciate your help.
zirano latt17y ago
using is nothing just to ensure it calls dispose method even exception is threw.

to share data among the child mdi forms, create a public property in MDI parent/container form and access that property through out all your child form.

public partial class MDIParentForm : Form
{
        public string SharedName { get; set; }
}

public partial class MDIChildForm1 : Form
{
        public SetShareName(string str)
        {        ((MDIParentForm)MdiParent).SharedName = str;
        }
}

public partial class MDIChildForm2: Form
{
        public string GetShareName()
        {        return ((MDIParentForm)MdiParent).SharedName;
        }
}