Sending data from one form to another form

[Ken]

To send the name of a form to another form. (or you could send any other kind of data)
Do the following:

Code:

//You will use a delegate that points to a function.

using System;
using System.Drawing;
using System.Windows.Forms;
using System.Data;


namespace TalkingToForms
{
public partial class formMain : Form
{
          public formColorChooser()
           {
             InitializeComponent();
           }

            //this is the declaration of the delegate type class named delPassDataToColor
            //the delegate contains a parameter, a String type named FormName
            //later we will make an instance of the delegate class named delPassToColor
            public delegate void delPassDataToColor(String FormName);


         //a mouse down event to trigger the delegate
         private void frmMain_MouseDown(object sender, MouseEventArgs e)
          {
            if (e.Button == MouseButtons.Right)
            {
               //a new form instance named NewfrmColorChooser
                formColorChooser NewformColorChooser = new formColorChooser();

                //now the delegate instance of type delPassDataToColor named del
                //the NewformColorChooser must have a public member named PassData
                delPassDataToColor del = new delPassDataToColor(NewformColorChooser.PassData);

                //now pass the string "main" to the PassData member of NewfrmColorChooser and show the form with the .ShowDialog member.
                del("main");
                NewformColorChooser.Show();
            }
        }
    }
}

Now the NewfrmColorChooser is just another form with the name frmColorChooser. It must have a member named PassData that accepts a string parameter.

namespace TalkingToForms
{
    public partial class formColorChooser : Form
    {
      
        public formColorChooser()
        {
            InitializeComponent();

        }
      
        //this is where the PassData member accepts the string. We send it the word "main".
        //so now the string FormName contains the string "main"
        public void PassData(String Name)
        {
           String FormName = Name;
        }
   }
}

I will show some more complicated ones where you can have a whole class of delegate with its own members.
Hope you enjoyed it. Have fun programming
Ken

[espirator]

Hi Ken;

Happy to see your new forum

i'd like to ask a question about this topic. I have two forms and i wanna connect them. First form is main form and i have a button to connect this form to the other form. I succeed it but my problem is that; in the 2nd form i have pictureBoxes and when i click these picturBoxes, i'd like to write some text in the richtextbox of the main form. I could'nt do it with changing "private" to "public static", the access way of the object.

Can u help me ?

Thanks

[Ken]

Hey good to here from you again. I hope you are doing well.

Yes you will need a delegate to send info back to the first form. Look at how the example does it and if you still need help then past the code for the click event on the second form and I will show you how to implement.

It will look something like this:

Code:

//declare the delegate inside form2
  public delegate void PassDataDelegate(String InfoToSend);


// make instance of delegate point to the public member on form1...make sure they have the same data type for the parameters
// this code will go inside the click event of the picture on form2
  PassDataDelegate del = new PassDataDelegate(Form1.PassData);
  del("string to send to form1.PassData member");

Let me know if this helps
Ken

[espirator]

i get this error

How can i make it correct?..

[Ken]

Yes

Go to form1 and enter the following member function

Code:

//this member will accept the data string that is passed from form2
public void PassData(String StringThatsPassed)
{
   textbox1.Text = StringThatsPassed;

}

This should get rid of the error for you.

Ken