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Want to take data from one form to use them as variable in an other

I'm almost done doing a Connect4 game with VS2012 using WinForms. Everything is working well but I wanted to bring the options for the user on a dedicated Start Menu window. On that menu I have two comboBoxes I need to take the text from to use them as a value for two variables in my other form (the game window). I also have one New Game button that should call a method from my other form if that's possible (basically, I made an "Initialization()" method in my game form and I'd like it to be launched when I click the "New Game" button on the other form).
I only found tutorials that show how to do very basic things from one form to an other (such as labeling texts) but I I didn't find an answer to my specific problem.
I used this in my main form to instantiate the menu form
public FormMenu myMenu;
myMenu = new FormMenu();
What I want to do is that I could do something like this in the other form :
amountOfRows = Int32.Parse(myMenu.comboBoxRows.Text);
amountOfColumns = Int32.Parse(myMenu.comboBoxColumns.Text);
Any idea how I could do that?

I would love to see some example code so I can help see where your confusion lies. WinForms requires the other form to be instantiated.
OtherForm form = new OtherForm();
Once the form is instantiated you should be able to run code from it.
EDIT:
Based on your implementation I would suggest making public methods within FormMenu that return these int values.
public int ReturnRows()
{
return Int32.Parse(myMenu.comboBoxRows.Text);
}
public int ReturnColumns()
{
return Int32.Parse(myMenu.comboBoxColumns.Text);
}
Then from the other form in which myMenu is instantiated you can call myMenu.ReturnRows() and myMenu.ReturnColumns()

The easiest way would be to store a reference to your form in the menue as a variable. (you already named it myMenu)
Then you should create the property/properties you need in the form an add a setter for the values. (see example here)
Last you update the form fields with
myMenu.property = newvalue;
That`s all about it

What is the best way to access things in a Form from another Form? C#

I was just wondering. If I have two forms.. Form 1 and Form 2 and you need to access a textbox, a label etc.. for example to make it visible or to change its text..
Which is the best way to access these from Form2?
Making a method in Form 1 like:
public void setTextBoxVisible(){
textBox1.Visible = true;
}
or making an accessor in Form 1, and change the visibility from Form 2, like:
In Form 2:
public TextBox TextBox1 {
get { return textBox1; }
}
In Form 1:
Form1 form1 = new Form1();
form1.TextBox1.Visible = true;
I know it may be a stupid question but I am still new to programming and I wish to know the best way I could do these things. Thanks :)

Option 1 is definitely better, because you are only exposing the part that you want to expose.
Not only are you leaving less room for error on part of the caller, but you are stating the intent of your method.
In option 2, all aspects of your control are accessibly and can be changed from outside code, not only the Visible property.
You could, if it suits your preference better, create a property:
public bool TextBox1Visible
{
get { return TextBox1.Visible; }
set { TextBox1.Visible = value; }
}

Programmers preference I think.. I always prefer method 1 as theres less room for error and if you want to change what it does in a lot of instances then its done in one line of code

In your 2nd scenario you are declaring read-only property , whereas in First approach you are exposing the functionality through a public function, which IMO is more clear and better approach.
EDIT:
One of the problem which I see with your first approach is that you can't stop a user from changing some property other than Visible. The user (developer) can mistakenly set the Text Property of your TextBox as well. e.g.
form1.TextBox1.Text = "Some new text";
The above is not a desired behaviour. (You only wanted to set Visible property)

Use a datamodel as a seperated class. Use the observer / MVVM pattern to get notified when the datamodel gets changed.

I assume that you have some action in Form2 that triggers the change to Form 1. Given your options I would got for 1. Another option is to consider events. Form1 subscribes to an event on Form2. When it gets triggered you can pass whatever you want to Form1 and have it carry out whatever updates or changes you want.

Custom event on object to change button state

I have 3 buttons on my Data Entry form, OK, APPLY, CANCEL.
This form is used to edit a doctor's details, things like first name, phone # etc...
I have one object doctorObj which at any given time is either empty (a new doctor) or an object pulled from a Linq query.
I deep clone the doctorObj to EditCopyDoctor which is of the same type but used for form editing (so if Cancel is hit, the database do not need to update).
What I want to achieve is observe the EditCopyDoctor for changes against the original doctorObj so
If(doctor.Changed() && doctor.IsNotNew)
{
ApplyButton.Enabled = true;
}
else
{
ApplyButton.Enabled = false;
}
So I thought writting an event to trigger when something changed on EditCopyDoctor is the best way to do it but I'm not sure how.
I can of course put the ApplyButton.Enabled code in the TextChanged events from the form but I was wondering if there are any quicker ways to do this, I don't really want to do this as there are 10+ textbox and other controls.

Since your "Doctor" type sounds like it's generated by LINQ to SQL/Entities you should find that it already implements the INotifyPropertyChanged interface. Therefore, you should just need to watch the PropertyChanged event and act accordingly.

How bad is the following snippet?

My question is simple: how bad is the following snippet of code? How would you do it?
CancelEventHandler _windowClosing;
private CancelEventHandler WindowClosing
{
set
{
clearEventHandlerList();
this.Closing += value;
_windowClosing = value;
/*
* if calling the method with null parameters,
* it will set up itself as the primary control on the Window
*/
_windowClosing(null,null);
}
get
{
return _windowClosing;
}
}
private readonly CancelEventHandler[] CONTROLS = null;
private int current = 0;
public InitializerForm()
{
InitializeComponent();
/*
* these are the handlers for the different controls,
* in the order of appereance to the user
*/
STATES = new CancelEventHandler[] { handler1, handler2, etc. };
WindowClosing = CONTROLS[0];
}
private void clearEventHandlerList()
{
foreach (CancelEventHandler c in CONTROLS)
{
this.Closing -= c;
}
}
private void handler1(object obj, CancelEventArgs e)
{
if (obj == null)
{
//hide every other control, but this one, also set up if necessary
}
else
{
//do something
WindowClosing = CONTROLS[++current]; // set the next control to show
e.Cancel = true;
}
}
The point would be that the code wouldn't close a form, but instead show another component on it, and the set the way to handle that (this is mobile platform, so clicking OK button on the top generates a closing event). This is because showing several forms (4 or 5) one after another to the user makes the app blink, and also very annoying, while replacing just components is much smoother. This model works, but seems very nasty, and I would like a cleaner way to handle this.
Update:
I updated the code sample so that variable names are somewhat speaky. Still, I'm convinced this is awful, (a) but not sure how much, and more importantly, (b) how to do it better.
Update 2:
So, it seems that the code is still a bit mysterious.
Now here's what the problem is:
I show the user a form, which instructs him what to do in several languages. He proceeds by clicking OK on the window. Next, I ask for his language, and then a few questions (where his/her GPS is, etc.) like this. After he could answer the questions (this shouldn't take more than a few seconds each), I show him a splash screen (I load stuff in a separate thread meanwhile), which has a picture. Showing these forms one after another makes the whole application start slow, and filled with UI lags.
Here's what I do to work around the lags: I put the content of the windows into panels, and put those panels one on another, and hide every one of them but the one that should be visible to the user. (current variable) Each of the windows does different things, so I need to change handler of the window closing event in addition. In this code the part which enables the panel is in the same function (handler1, handler2, etc.) with the part which handles the window closing event. If the arguments are null, it does the former, if it isn't (that means it was triggered by the user) it does the latter.
I need an extensible solution to this so that I can insert and remove dialogs anytime I want (the order and the pointers to the functions are stored in the CONTROLS field, and this seems to be very convenient, if you actually understand it. Although it is never easy to change the entire content of a form, there ought to be a simpler way to do this, as well a nicer one, that is what I'm looking for.
I hope this time I could explain how the model works.

I think it might be theoretically possible to make that code more delightfully diverting, perilously puckish, jovially jeopardous, cheerily chancy and unwarily whimsical but it would require some serious thought.

somehow your code makes me want to cry, i´m sorry. i read it twice and all i know about it is that it "doesStuff" with "STATES".
if you really want some help on this one you will have to work on it yourself first...

Use, XML! It's human-readable!
More seriously-
It seems like you're trying to create some sort of configuration wizard, so I'd start by researching that. Regarding your particular solution, I generally advocate very strongly against the "layered panel" approach. I do so because I maintain apps written by people who found this approach, or the related "hidden tabs on a tab control" approach, to be a good idea. It's not, and maintainers will curse your name for years to come.
That being said, what alternatives are there? Well, one alternative is what you've already dismissed because of its "flicker". I'd say that, in general, the flicker isn't that big of a deal for a quick and dirty application. It might be a good idea to make sure that your new window is called up before closing the old one, for example. (I'm assuming this is possible, I haven't developed on a mobile device.)
Another possibility might be a less-evil version of your layered panels. Instead of throwing a half-dozen panels into one form, create a separate user control for each wizard page and then add/remove the user controls to a containing form. This can avoid your flicker and will prove to be much easier to maintain because each page is in a different control. This might also ease any subsequent "Back" button functionality and make your data structures more naturally defined because those user controls will be associated with a specific logical bit of data. It's still not ideal, but it's probably good enough for a one-off solution.
A third technique, if you foresee extensive wizard modification as the product matures, might be to generalize the creation of your user controls by defining them in a more logical/declarative manner (e.g. via XML). If you dynamically generate sensible controls based on XML, then modifying the panels might be as easy as diving into your XML and doing something like:
<Questions>
<Question type="Text"> <!-- generate a textbox for the answer field -->
Favorite Color:
</Question>
<Question type="Number" range="0-255"> <!-- Maybe this is a spinner -->
The answer to life, the universe, and everything:
</Question>
</Questions>
That's just off the top of my head, and completely overkill for any one-off application, but it's a possibility.

Now, let me caveat this by saying this might work, but it may not be the answer to your real problem - that of a slow and unresponsive UI when you have a lot of forms. The real answer may be to just go ahead and do all separate forms, but have each form load its child forms in a background thread while the user is staring at the first form.
But assuming you're still set on this, I'd start off by making a separate class just to handle the Panel stacking/hierarchy. Call it PanelManager. You would instantiate the PanelManager and associate it with the main form, then add Panels to it (perhaps keyed to a String) and set the order. In the main form, have the closing handler call PanelManager.CloseCurrentPanel() and if there are no more Panels to show then it's time to close the main form.
Time for pseudo-code! Here's a quick idea for the class, i'll leave it to you to implement it:
public class PanelManager {
// constructor
public PanelManager (Form ownerForm);
// short-cut properties
public Panel this[int idx]
{ get; set; }
public int Index
{ get; set; }
// main functionality
public int AddPanel (Panel p);
public void SetPanelOrder (Panel p, int idx);
public void RemovePanel (Panel p);
public void RemovePanelAt (int idx);
// shows the first Panel
public void Show ();
// shows Panel[idx]
public void Show (int idx);
// adds the panel to the top of the stack and displays it
// returns the index of the panel
public int AddPanelAndShow (Panel p);
// hides the current panel, displays the one underneath it
// returns false if there are no more panels
public bool HideCurrentPanel ();
}
in the constructor for the main form, instantiate it by new PanelManager (this), then in the closing event handler, call panelManager.HideCurrentPanel () and then figure out whether or not you need to close it after that.

Winform & user control - C#

I have a Form and a UserControl. The UserControl has a menu, and the form has a tabstrip (General, Food, Vitamins etc).
In the UserControl, I have the following code: (Form name is frmForm, the tab names in the form are tabGeneral,tabFood, tabVitamins)
frmForm fm=new frmForm();
fm.tabMain.Selected=tabVitamins;
I call these line from the UserControl to capture the tab to get selected on the form, but it does not select the vitamins tab.
Where am I going wrong? I have access specifier as Protected Internal for tabs in the form.
Please advice.
Thanks,
Karthick

When you write new frmForm(), you're creating a completely new instance of frmForm, which is then discarded.
To get the frmForm instance that holds your control, call the FindForm() method and cast to frmForm.
For example:
frmForm myForm = FindForm() as frmForm;
if(myForm != null)
myForm.tabMain.SelectedTab = myForm.tabVitamins;
If the control is on some other form, this code won't do anything.
By the way, Hungarian notation is frowned upon in .Net.
Your form should probably be named something like MainForm.

SLaks has correctly pointed out your fundamental error, and given you a valid example of a way, via a call to the method 'FindForm, to get the Form the UserControl is sited on.
It may be valuable to you to keep in mind that a UserControl (and all Controls) also has a 'Parent property, but, of course, a UserControl could be placed inside another Control on a Form (like your UserControl could be inside a Panel on the Form) : in that case the UserControl's Parent would be the control it's inside on the Form (like, a Panel), not the Form itself, but 'FindForm will do the right thing to get you the Form it's on.
However you are calling a Method every time you use 'FindForm, and "best practice" suggests that what you want to do is to "inject" a reference to the Form into the UserControl at run-time so that it can always access its Form property easily, without calling a 'Method.
In your example, on a practical level, this (calling the Method) may make almost no difference in performance, but, imho, as you get to a place with WinForms and .NET where you might have a UserControl that will need access to its Parent Form very frequently, this will pay off, and it's a better way to structure your code in the long run, for maintenance.
Wes showed you one way you can "embed" (inject) the UserControl's hosting Form : using an overloaded constructor for the UserControl. But that requires you to modify the Designer.cs file in standard WinForms, and I strongly advise you against that, even though it will work. Particularly if you are just "getting your feet on the ground" in .NET, I strongly advise you against modifying it, or anything having to do with the Form's constructor and its internal call to : InitializeComponent();
Also, as you progress with WinForms you are going to meet many situations where you are going to want instances of "objects" (a Control, a Form, an instance of a Class) to contain references to other instances of "objects.
If you can understand and use one simple use of "injection" here, you are going to make progress to make yourself ready to handle more complex .Net programming in the future.
Another way is to put a Public Property in the UserControl that can be set in code from the MainForm. In the UserControl something like :
private frmForm ParentForm;
public frmForm UCParentForm
{
set { ParentForm = value; }
}
So then in your main form's code, perhaps in the Load event like this :
private void frmForm_Load(object sender, EventArgs e)
{
TheUserControl.UCParentForm = this;
}
or when you need to, you set the UserControl's 'ParentForm property once. So you have eliminated using the method 'FindForm().
In this case, if you only want access to a specific control on the UserControl's Parent Form, like a TabControl, you might consider that you want to make the Property you set of type TabControl, rather than Form : the same coding technique shown above can be used in the UserControl :
private TabControl mainFormTabControl;
public TabControl MainFormTabControl
{
set { mainFormTabControl = value; }
}
imho, it is when you are creating UserControls dynamically at run-time, using an overloaded constructor, as Wes suggests, is the best strategy. And using overloaded constructors has many, many others uses in .NET that you'll get into.
good luck !

You should not be creating a new frmForm() inside the user control. You could pass a reference to the frmForm to the user control.
In your user control constructor try something like this.
private frmForm fm;
public YourUserControl(frmForm fm)
{
this.fm = fm;
}
Then you could use.
fm.tabMain.Selected=tabVitamins;
Does that help?