Develop Reference

c# label to receive information from private method(toolbox value)

I've created a new form, in which I have a toolbox. When I press a button in that form, it should relay that information that has been entered by the user(toolboxbox value) to the main form, in which it should say that piece of information in a label.
Since the method to create that username from the toolbox is private, I cannot access it from any other way. Making it public does not seem to make a difference, neither does get,set (from the way I've been trying to atleast).
Picture that may help explaining it:
Code (in which to create user):
namespace WindowsFormsApplication3
{
public partial class Newuserform : Form
{
public Newuserform()
{
InitializeComponent();
}
private void buttonCreateUser_Click(object sender, EventArgs e)
{
string uname = textboxUsername.ToString();
}
public void Unamecreate()
{
}
}
}
Form1 Code (To receive created user):
namespace WindowsFormsApplication3
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void aboutToolStripMenuItem1_Click(object sender, EventArgs e)
{
Aboutform form2 = new Aboutform();
form2.Show();
}
private void newLocalUserToolStripMenuItem_Click(object sender, EventArgs e)
{
Newuserform formnewuser = new Newuserform();
formnewuser.Show();
}
}
}

you have a lot of options.
One way is to create an event and handle it in the main form.
public partial class Newuserform : Form
{
//the public property
public event EventHandler<string> UnameChanged;
public Newuserform()
{
InitializeComponent();
}
private void buttonCreateUser_Click(object sender, EventArgs e)
{
if (UnameChanged != null)
UnameChanged(textboxUsername.ToString()); //fire the event
}
}
Now, to "handle" the event, do the following in your main form:
private void newLocalUserToolStripMenuItem_Click(object sender, EventArgs e)
{
Newuserform formnewuser = new Newuserform();
formnewuser.UnameChanged += Handler;
formnewuser.Show();
}
private void Handler (object sender, string Uname)
{
// do something wit the new Uname.
}
note: recreating the Newuserform will require to cleanup previous attached resources.

Object reference is required for the non static field

namespace Pong
{
public partial class Menu : Form
{
public Menu()
{
InitializeComponent();
}
private void pictureBox1_Click(object sender, EventArgs e)
{
}
private void PlayButton_Click(object sender, EventArgs e)
{
PongForm form = new PongForm();
PongForm.Show();
this.Close();
}
private void ExitButton_Click(object sender, EventArgs e)
{
this.Close();
}
}
}
Can someone explain why I'm getting an error? I've had a look online and think it should work. I'm trying to change to a new form on button click.

In this function you should refer form, not PongForm:
private void PlayButton_Click(object sender, EventArgs e)
{
PongForm form = new PongForm();
form.Show();
this.Close();
}

Change "PongForm.Show();" to "form.Show().
To eloborate: you are attempting to call the class, not the instance you created.

to just add to what others have said. you probably don't want multiple of the same forms open. I cant comment or I would have done that instead. hope this solves your problem.
if (Application.OpenForms["PongForm"] != null)
{
Application.OpenForms["PongForm"].WindowState = FormWindowState.Normal;
Application.OpenForms["PongForm"].BringToFront();
}
else
{
PongForm form = new PongForm();
form.Show();
}

C# Calling a method

I have a form with multiple instances of a user control on it.
I've assigned the following:
Switch.armySwitchCloseButton.Click += armySwitchClose;
So when one of those instances is pressed, I call the following method:
void armySwitchClose(object sender, EventArgs e)
The above method has a bunch of additional code in it which isn't required for here.
Now what I need to do is from another button, call this above function from every instance.
How can I do this?
Many Thanks

In constructor of each user control you can pass the same instance of some object who knows how to run this method
void armySwitchClose(object sender, EventArgs e)
Then, you call this method inside each event method, for ex:
Public Class UserControl(){
private MakeEvent makeEvent;
Public MyClass(MakeEvent makeEvent)
{
this.makeEvent = makeEvent;
Switch.armySwitchCloseButton.Click += armySwitchClose;
}
void armySwitchClose(object sender, EventArgs e)
{
makeEvent.armySwitchClose(sender,e);
}
}
Public Class MakeEvent() {
void armySwitchClose(object sender, EventArgs e)
{
//the real implementation
}
}
Hope this solve your problem.
Oh, I think I get your problem wrong... When you click in one button all the other events in others UC must be triggered, right? This problem can be solved with the Observer Pattern
Public Interface IObserver
{
void armySwitchClose(object sender, EventArgs e);
}
Public UserControl1: Observer
{
void armySwitchClose(object sender, EventArgs e)
{
//implementation UC1
}
}
Public UserControl2: Observer
{
void armySwitchClose(object sender, EventArgs e)
{
//implementation UC2
}
}
In button UC:
Public UserControlButton
{
private List<IObserver> observers;
public void addObserver(IObserver observer)
{
observers.Add(observer);
}
public void button_clickedEvent(object sender, EventArgs e)
{
foreach(IObserver observer in observers)
{
observer.armySwitchClose(object sender, EventArgs e);
}
}
}
In form with all buttons you call addObserver adding each user control.

Add items from a listbox to another listbox on another form

Here is my code.
private void PlaceOrder_Click(object sender, EventArgs e)
{
MenuBox.Items.Clear();
TotalBox.Items.Clear();
total.Clear();
ordertotal = 0;
}
I want to add what is in the menu box to a another list box on another form.
Update
(added by jp2code)
Form1 (Main):
namespace WindowsFormsApplication1 {
public partial class RESTAURANT : Form
{
double soup = 2.49;
double ordertotal;
public RESTAURANT()
{
InitializeComponent();
}
private void RESTAURANT_Load(object sender, EventArgs e)
{
}
private void Add_Click(object sender, EventArgs e)
{
MenuBox.Items.Add("Soup");
TotalBox.Items.Add(String.Format("{0:C}", soup));
ordertotal += soup;
total.Text = Convert.ToString(String.Format("{0:C}", ordertotal));
}
private void TotalBox_SelectedIndexChanged(object sender, EventArgs e)
{
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
}
private void PlaceOrder_Click(object sender, EventArgs e)
{
new AreYouSure().Show();
this.Show();
MenuBox.Items.Clear();
TotalBox.Items.Clear();
total.Clear();
ordertotal = 0;
}
}
}
Form2 (Confirmation)
namespace WindowsFormsApplication1 {
public partial class Confirmation : Form
{
public Confirmation()
{
InitializeComponent();
}
private void label1_Click(object sender, EventArgs e)
{
}
private void Confirmation_Load(object sender, EventArgs e)
{
}
private void MenuBox_SelectedIndexChanged(object sender, EventArgs e)
{
}
}
}
When clicking the 'Send Order' button the items from 'MenuBox' in form 1 need to be sent to the 'MenuBox' in form 2

OtherForm.OtherListbox.Items.Clear();
foreach(var itm in MenuBox.Items)
OtherForm.OtherListbox.Items.Add(itm);

Form1 (Main):
namespace WindowsFormsApplication1 {
public partial class RESTAURANT : Form
{
double soup = 2.49;
double ordertotal;
public RESTAURANT()
{
InitializeComponent();
}
private void RESTAURANT_Load(object sender, EventArgs e)
{
}
private void Add_Click(object sender, EventArgs e)
{
MenuBox.Items.Add("Soup");
TotalBox.Items.Add(String.Format("{0:C}", soup));
ordertotal += soup;
total.Text = Convert.ToString(String.Format("{0:C}", ordertotal));
}
private void TotalBox_SelectedIndexChanged(object sender, EventArgs e)
{
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
}
private void PlaceOrder_Click(object sender, EventArgs e)
{
new AreYouSure().Show();
this.Show();
MenuBox.Items.Clear();
TotalBox.Items.Clear();
total.Clear();
ordertotal = 0;
}
}
}
Form2 (Confirmation)
namespace WindowsFormsApplication1 {
public partial class Confirmation : Form
{
public Confirmation()
{
InitializeComponent();
}
private void label1_Click(object sender, EventArgs e)
{
}
private void Confirmation_Load(object sender, EventArgs e)
{
}
private void MenuBox_SelectedIndexChanged(object sender, EventArgs e)
{
}
}
}
When clicking the 'Send Order' button the items from 'MenuBox' in form 1 need to be sent to the 'MenuBox' in form 2

It is better that the controls on your other form (ListBox, in this case) are set to Private by default.
In that case, you would either need to set the control's visibility to Public (bad form, in my opinion) or create a method in your other form to accept the parameters from your form.
Consider something like this:
public void ListBoxData(object[] array)
{
listBox1.Clear();
listBox1.AddRange(array);
}
To get the data or selected item information back to your main form, you would likewise create another public object that you could check, like the property below:
public object SelectedItem { get { return listBox1.SelectedItem; } }
I hope that is what you were looking for.
UPDATE:
Using the code you supplied in the post below, I can see you do not have anything in your Confirmation form to send data to, much less a way to pass that information.
If you had a ComboBox, you could do something like follows:
public partial class Confirmation : Form
{
private ComboBox comboBox1;
public void AddRange(object[] array)
{
comboBox1.Items.AddRange(array);
}
}
That does not place the ComboBox anywhere on your form. You would need to work that out.
With that done, I'm guessing you need to edit your PlaceOrder_Click routine:
private void PlaceOrder_Click(object sender, EventArgs e)
{
//new AreYouSure().Show();
//this.Show();
using (var obj = new Confirmation())
{
var list = new List<object>(MenuBox.Items.Count);
foreach (var o in MenuBox.Items)
{
list.Add(o);
}
obj.AddRange(list.ToArray());
if (obj.ShowDialog(this) == DialogResult.OK)
{
MenuBox.Items.Clear();
TotalBox.Items.Clear();
total.Items.Clear();
ordertotal = 0;
}
}
}
If you are struggling with this, you might need to look into some C# Windows "multiple forms" tutorials.
Here is a YouTube (that I did not sit all the way through): https://www.youtube.com/watch?v=qVVtCPDu9ZU

How do i resolve an expected class, delegate, enum, interface, struct compiling error?

I am getting this error at private void ...
This a real simple program that I want to display a message using a string variable.
namespace WindowsFormsApplication6
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
{
string greetme;
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
greetme = textbox1.text;
}
private void button1_Click(object sender, EventArgs e)
{
MessageBox.Show("Hello {0}", greetme);
}
}
}

Just remove the parenthesis around your declaration of greetme:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
string greetme;
private void textBox1_TextChanged(object sender, EventArgs e)
{
greetme = textbox1.text;
}
private void button1_Click(object sender, EventArgs e)
{
MessageBox.Show("Hello {0}", greetme);
}
}

These errors almost always mean that you have brackets where you shouldn't. In this situation, it's the brackets/code after your "Public Form1()" method. There is no method declaration and no need for brackets there.