C#.net winform : How to access form event in user control ??

koba Tirth

I have created one winform, Load user controle on that form and adding text box run time in that controle. I have created one event to handle text_change of that text box, but can not access that event, because event was created on winform and contrle can not access it.

How can fix this issue, Kindly help in this regard.

Code is given below for ready refereence.

Thanks

Form :

public class form1:Form

{

public form1()

{

InitializeComponent();

}

usercon uscon=new usercon();

private void form1_Load (object sender, EventArgs e)

{

uscon.Parent=panel1;

}

private void txt_textchange(object sender, EventArgs e)

{}

}

User control :

public class usercon : UserControl

{

public usercon()

{

InitializeComponent();

}

private void btn_multi_Click(object sender, EventArgs e)

{

TextBox txtbox = new TextBox();

txtbox.Name = dynamictxt";

txtbox.Location = new Point(59, 30);

txtbox.Size = new System.Drawing.Size(188, 20);

Panel1.Controls.Add(txtbox);

}

11 Replies

Know the answer? Post it — somebody with the same question will find it here.

Amit Gupta9y ago
Glad to help you!!

Please show your gratitude by accepting the correct answer.
0
koba Tirth9y ago
thanks so much sir
0
Amit Gupta9y ago
C# doesnot allow to call the event like this.

You have to create an EventHandler in UserControl class and then call it from the main form.

However, I donot have your code to make changes, I had just made some ammendments to the existing code of mine and has been attached.

I'll try to append that function in your partial code, hope that works
User control :
public class usercon : UserControl
{
public usercon()
{
     InitializeComponent();
}
//creating EventHandler
public delegate void OnTextChangedEventHandler(object sender, EventArgs e);

        private OnTextChangedEventHandler textChanged;
        public event OnTextChangedEventHandler TextChanged
        {
            add { textChanged += value; }
            remove { textChanged -= value; }
        }

private void btn_multi_Click(object sender, EventArgs e)
{
  TextBox txtbox = new TextBox();
  txtbox.Name = dynamictxt";
  txtbox.Location = new Point(59, 30);
  txtbox.Size = new System.Drawing.Size(188, 20);
  txtbox.TextChanged += Txtbox_TextChanged;
  Panel1.Controls.Add(txtbox);
}

//Invoking the event
private void Txtbox_TextChanged(object sender, EventArgs e)
        {
            if (textChanged != null)
                textChanged.Invoke(sender, e);
        }
}
FORM :
public class form1:Form
{
public form1()
{
InitializeComponent();
}
usercon uscon=new usercon();
private void form1_Load (object sender, EventArgs e)
{
uscon.Parent=panel1;
//creating the text changed event, that we had generated in the user control class
uscon.TextChanged+=txt_textchange;
}
private void txt_textchange(object sender, EventArgs e)
{
     // Finally, we get the value in the below variable
    var TextBoxValue = ((TextBox)sender).Text;
}
The same has been attached for your consideration.
0
koba Tirth9y ago
Program.CS
static class Program
{
///
/// The main entry point for the application.
///
[STAThread]
static void Main()
{

Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
}

FORM :
public class form1:Form
{
public form1()
{
InitializeComponent();
}
usercon uscon=new usercon();
private void form1_Load (object sender, EventArgs e)
{
uscon.Parent=panel1;
}
private void txt_textchange(object sender, EventArgs e)
{}
}

User control :
public class usercon : UserControl
{
public usercon()
{
InitializeComponent();
}
private void btn_multi_Click(object sender, EventArgs e)
{
TextBox txtbox = new TextBox();
txtbox.Name = dynamictxt";
txtbox.Location = new Point(59, 30);
txtbox.Size = new System.Drawing.Size(188, 20);
txtbox.TextChanged += new System.EventHandler(form1.txt_textchange);
Panel1.Controls.Add(txtbox);
}
}

highlight line find the textchange event but event was stored in form1 so give some error.
this code use my form please check it..
thanks..
0
Amit Gupta9y ago
Hey,

I had some demo working code that might useful to you.

Please find the attachment.

Make changes according to your requirement.

Good Luck !!
0
Amit Gupta9y ago
Please share what you have done so far or better zip and share your project.

Well this was quite most classic question. Have you tried the code that we have provided in the link?
0
koba Tirth9y ago
after load i was created textbox and then given event.

load time it's possible but after load how can possible ..
0
Amit Gupta9y ago
When you are adding only textboxes, then why not consider implementing this in the parent form itself regardless of utilizing user control.

This would make your task easier

Moreover, if you want to call the event from user control, then you have to put an array of control with public access specifier and call it from the parent form to create an event

Check the below link fyi
https://www.codeproject.com/Questions/385770/how-to-access-usercontrol-textbox-values-to-parent
0
koba Tirth9y ago
same form i m access easily but some how event not same page both r the different.

so i can't easily write
textbox.textchange += new System.EventHandler(this.Button_Click);
0
Khaja Moizuddin9y ago
Refer http://stackoverflow.com/questions/7880850/how-do-i-make-an-event-in-the-usercontrol-and-have-it-handeled-in-the-main-form https://msdn.microsoft.com/en-us/library/system.windows.forms.usercontrol_events(v=vs.110).aspx http://sharepointpals.com/post/Grab-UserControl-custom-event-in-a-Winform
0
Amit Gupta9y ago
Quite classic question, check the below link
https://www.aspsnippets.com/Articles/Add-Dynamic-TextBox-Label-and-Button-controls-with-TextChanged-and-Click-event-handlers-in-Windows-Forms-WinForms-Application.aspx

Hope this helps
0