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Load popup form cross thread

I'm having trouble manipulating forms when from another thread.
I've overcome the issue by loading the form at runtime, showing it then hiding it. This means the form is created on the right thread and can be manipulated using invokes.
This is not the right way to do it. I have 3 problems that come from using this method
I can't spawn another popup box I have to use the one I created at runtime
The forms flash briefly on load - now that I have 3 forms its pretty obvious what I'm doing.
I have to use a variable bool to hold if the popup is open or not.
If anyone could point me in the right direction It would be much appreciated. Currently my code looks like:
On Main form Load:
CallerIDfrm = new frmCallerID();
CallerIDfrm.Show();
CallerIDfrm.Hide();
to manipulate the popup Im using
delegate void StringArgReturningVoidDelegate1(string CallerIDnum, string CallerIDname, string ContactID);
private void CallerID(string CallerIDnum, string CallerIDname, string ContactID)
{
if (CallerIDfrm.InvokeRequired)
{
StringArgReturningVoidDelegate1 d = new StringArgReturningVoidDelegate1(CallerID);
CallerIDfrm.Invoke(d, new object[] { CallerIDnum, CallerIDname, ContactID });
}
else
{
if (ContactID != null || ContactID != "0")
{
CallerIDfrm.ContactID = ContactID;
}
CallerIDfrm.Mainfrm = this;
CallerIDfrm.TopLevel = true;
CallerIDfrm.TopMost = true;
CallerIDfrm.lblCallerIDname.Text = CallerIDname;
CallerIDfrm.lblCallerIDnum.Text = CallerIDnum;
CallerIDfrm.Show();
CallerIDOpen = true;
}
}
To Hide the popup until required again im using:
delegate void StringArgReturningVoidDelegate2();
private void CallerIDClose()
{
if (CallerIDfrm.InvokeRequired)
{
StringArgReturningVoidDelegate2 d = new StringArgReturningVoidDelegate2(CallerIDClose);
CallerIDfrm.Invoke(d, new object[] { });
}
else
{
try
{
CallerIDfrm.Hide();
CallerIDOpen = false;
}
catch
{
}
}
}
I've tried otherways but the Popup loads as if it is not responding and I loose access to the popup.
Ultimately I'd like to be able to spawn multiple popups and have the ability to close them from the Main Form.

What I gather from your question: You have an caller api/lib/class and you like to show CallerId on a popup form when a call is received. Have a look at Events and Event Driven programming.
The following codes has not been tested, I wrote it from top of my head. Might not compile, they are here to show an example:
Create an CallReceived event in api/lib class as follows:
public event EventHandler<CallReceivedEventArgs> CallReceived;
protected void OnCallReceived(EventArgs e)
{
var handler = CallReceived;
if (handler != null)
handler(this, e);
// Note: For C# 6.0 and later, above statements can be simplified to
// CallReceived?.Invoke(this, e);
}
Note: If you don't have access to this api/lib code, create a Gateway class and put your event in there along with mechanism to trigger it.
Also create a CallReceivedEventArgs, this will be used to transfer event data:
public class CallReceivedEventArgs : EventArgs
{
public string CallerIDnum {get; set;}
public string CallerIDname {get; set;}
public string ContactID {get; set;}
}
Now, in your api/lib class raise this event whenever a call is received:
// a call received, replace dummy values with actual values
OnCallReceived(new CallReceivedEventArgs() { CallerIDnum="5554443322", CallerIDname="SOME_NAME", ContactID="SOME_CONTACT" });
Finally in your GUI form, register to said event and process accordingly.
// inside your main form class
private CallerAPI callerApi = new CallerAPI();
// somewhere inside you main form class, register to event
// from your use case, I would place it inside Main Form's constructor
callerApi.CallReceived += callerApi_Callreceived;
// receive event
void callerApi_Callreceived(object sender, CallReceivedEventArgs e)
{
var callerIDnum = e.CallerIDnum;
// etc.
// show callerId form with details
// you need to change frmCallerID's constructor accordingly
CallerIDfrm = new frmCallerID(e.CallerIDnum, CallerIDname, ContantID);
// to be able to track opened popups, you can store them inside a list
// private List<Form> openPopupList = new List<Form>();
//
// alternatively, you can assign CallerIDnum to form's name property
// and store these inside a List<string> instead of List<Form>
openPopupList.add(CallerIDfrm);
CallerIDfrm.Show();
}
Don't forget to unregister from event.
callerApi.CallReceived -= callerApi_Callreceived;
To wrap it up:
I can't spawn another popup box I have to use the one I created at runtime
You can create and show multiple frmCallerID, independent from each other.
The forms flash briefly on load - now that I have 3 forms its pretty obvious what I'm doing.
Since new approach creates CallerID forms based on events, you won't see these form flashing. It'll open whenever a CallReceived event is received.
I have to use a variable bool to hold if the popup is open or not.
A better approach would be: Register to forms FormClosed event, and remove from openPopupList accordingly.
frmCallerID.FormClosed += frmCallerID_FormClosed;
void frmCallerID_FormClosed(object sender, EventArgs e)
{
// remove form from openPopupList
frmCallerID closedPopup = (frmCallerID) sender;
openPopupList.remove(closedPopup);
}

Homework how to pass values from one form to an object in a list in another form

I have the following snippet of code that allows me to pull the properties from an object in my list and assign them to variables in other forms. However, I need to be able to pull the data from my variables in the other form and use those to set the properties of the given object.
My class Account is used to populate my list accounts. On my next form AccountMenu I have a class Variables1 that contains accessible variables that are used throughout the rest of my forms to keep track of the checking balance and saving balance. When logging off from the AccountMenu, I want to be able to pass the values from Variables1 to the account that was initially used.
I know how to pass variables from one form to another, but I'm not really sure how to update the form automatically, without a button, on the original form. Thus, the solution that I see is that I have a button on my AccountMenu form that "logs" the user out, via this.close(); Additionally, I guessed that under that button, I need to have some code that assigns the variables as properties to the object. I'm just not sure how I can access the set properties of the object, since it is dynamically called with the code below.
Can someone help me figure out what I need to do? Below is some of the relevant code so that you can see how I have things set up. I am just not sure how to access "matches" from the other form in order to update that specific object properties. Thank you, anyone, who can help!
//variable that will be used to check textbox1.Text
string stringToCheck;
//array of class Account
List<Account> accounts = new List<Account>();
public MainMenu()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
//set value to user's input
stringToCheck = textBox1.Text;
//set a var that only returns a value if the .Name already exists
var matches = accounts.FirstOrDefault(p => p.Name == stringToCheck);
//check through each element of the array
if (matches == null)
{
accounts.Add(new Account(stringToCheck));
textBox1.Text = "";
label3.Visible = true;
}
else if (matches != null)
{
//set variables in another form. not sure if these are working
Variables1.selectedAccount = matches.Name;
//is this calling the CheckBalance of the instance?
Variables1.selectedCheckBalance = matches.CheckBalance;
//same thing?
Variables1.selectedSaveBalance = matches.SaveBalance;
//switch to form
AccountMenu acctMenu = new AccountMenu();
this.Hide();
acctMenu.Show();
}
}

As per my understanding I think what you required is kind of trigger on your parent form that needs to be called from your child application.
If that is what you required than you can go with defining an event on your AccountMenu form. and register this event from your Accounts form.
Than simply raise this event from your AccountMenu subform.
Deletegates and Events are really works like magic :)
Let me show you some code how to do this.
Code required in AccountMenu window:
public delegate void PassDataToAccounts(string result);
public event PassDataToAccounts OnPassDataToAccount;
protected override void OnClosing(System.ComponentModel.CancelEventArgs e)
{
if (OnPassDataToAccount != null)
OnPassDataToAccount("result");
base.OnClosing(e);
}
Code required in Accounts window button1_Click event where the AccountMenu will open:
//set variables in another form. not sure if these are working
Variables1.selectedAccount = matches.Name;
//is this calling the CheckBalance of the instance?
Variables1.selectedCheckBalance = matches.CheckBalance;
//same thing?
Variables1.selectedSaveBalance = matches.SaveBalance;
//switch to form
AccountMenu acctMenu = new AccountMenu();
acctMenu..OnPassDataToAccount += childwindow_OnPassDataToAccount;
this.Hide();
acctMenu.Show();
}
void childwindow_OnPassDataToAccount(string result)
{
if (result == "result")
{
// Processing required on your parent window can be caried out here
//Variables1 can be processed directly here.
}
}

C# Take combobox item from one form and add its name as text to another

Ok so I'm attempting to create a simple game. In a nutshell it's a resource management game where the player will attempt to manage a thieves guild. In regards to running missions I've created a Thief class, a new instance of which is created when a new thief is recruited. I have coded within the thief class the ability to gain experience and level up.
Here's my specific problem:
I want the player to be able to select which thief/thieves to send on a mission. I have thought about it and figured that opening a new form and populating it with checkboxes is the easiest way to allow this. These checkboxes will be related to a List<thief> of thieves, the player then checks the thieves s/he wants to send and these are then stored in another List<thief> and passed on to the run mission function.
I've built a separate project with the intention of testing and playing around with this before putting it into the main program. The test project consists of two forms: The first (frmMain) with a textbox to hold the selected options and a button to open the second form (frmSelect). Currently I can open and populate the second form (frmSelect) but when I try to add the checked options to the textbox I simply...well can't.
So far I have tried directly accessing the textbox by typing frmMain.txtOptionsDisplay in the cs file of frmSelect but it causes the following error:
An object reference is required for the non-static field, method or
property
I tried to create a new form in frmSelect and make it equal to the active instance of frmMain with: Form frmTemp = frmMain.ActiveForm; and then alter the textbox using frmTemp as a go-between but that produced the error:
'System.Windows.Forms.Form' does not contain a definition for
'txtOptionsDisplay'.
Having searched both google and stackoverflow forums I've encountered answers that I either have never heard of (Threading) or answers that I kind've recognise but can't interpret the code pasted to make it relevant to my problem (delegates).
Any advice or pointers would be fantastic.
EDIT:
frmMain code:
public frmMain()
{
InitializeComponent();
selections.Add("Option 1");
selections.Add("Option 2");
}
private void btnClick_Click(object sender, EventArgs e)
{
frmSelectOptions.Show();
int length = selections.Count();
for (int i = 0; i < length; i++)
{
CheckBox box = new CheckBox();
box.Text = selections[i];
box.AutoSize = true;
box.Location = new Point(50, 50*(i+1));
frmSelectOptions.grpControls.Controls.Add(box);
}
}
public void updateText(string option)
{
txtOptionsDisplay.Text += option;
}
}
frmSelect code:
public List<CheckBox> selectedOptions = new List<CheckBox>();
Form frmTemp = frmMain.ActiveForm;
public frmSelect()
{
InitializeComponent();
}
private void btnSelect_Click(object sender, EventArgs e)
{
foreach (CheckBox box in grpControls.Controls)
{
if (box.Checked == true)
selectedOptions.Add(box);
}
this.Hide();
}
}
I hope this formats correctly... I'm kinda new and don't know how to indent. Oh look there's a preview...
Does this help?

Your problem is that controls defined within a form by default receive the private access identifier. Hence you could just add a property along the lines of
public ControlType ProxyProperty {
get {
return txtOptionsDisplay;
}
}
Besides from that you should think about wether what you're trying is actually a good solution. Manipulating forms from one to another will become a huge clusterfuck in terms of maintenance later on.

I'd suggest using the Singleton pattern for your frmMain. This will help safeguard you from accidentally launching another instance of frmMain and at the same time, will give you access to frmMain's objects. From there, you can either write accessors to Get your txtOptionsDisplay or you can make it public. Below is an example:
public class frmMain
{
private static frmMain Instance = null;
private static object LockObj = new object();
public static frmMain GetMain()
{
// Thread-safe singleton
lock(LockObj)
{
if(Instance == null)
Instance = new frmMain();
return Instance;
}
}
public string GetOptionsDisplayText()
{
return txtOptionsDisplay.Text;
}
}
public class frmSelect
{
private void frmSelect_Load(object sender, EventArgs e)
{
// Set whatever text you want to frmMain's txtOptionsDisplay text
txtDisplay.Text = frmMain.GetMain().GetOptionsDisplayText();
}
}
If you do go this route, don't forget to update Program.cs to use frmMain's singleton.
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
// Application.Run(new frmMain()); - Old method
Application.Run(frmMain.GetMain());
}

Passing string between two forms

I have a problem in passing a string value between two forms.
First I created public string sanacode which I assign the value passed in form 2
Form 1 code
AnalysisEdit ae = new AnalysisEdit();
int Row = dataGridView1.CurrentRow.Index;
ae.sanacode = dataGridView1[0, Row].Value.ToString();
ae.Show();
Form 2 constructor code
public AnalysisEdit()
{
InitializeComponent();
MessageBox.Show(sanacode,);
}
it shows me nothing

Change you constructor from
public AnalysisEdit()
{
InitializeComponent();
MessageBox.Show(sanacode);
}
to
public AnalysisEdit(string sanacode)
{
InitializeComponent();
MessageBox.Show(sanacode);
}
form call
int Row = dataGridView1.CurrentRow.Index;
AnalysisEdit ae = new AnalysisEdit(dataGridView1[0, Row].Value.ToString());
ae.Show();

The issue is that you're not calling things in the correct order. The form 2 constructor code will be called on line 1 of the form code, or AnalysisEdit ae = new AnalysisEdit(); However, this is before the assignment that takes place on line 3: ae.sanacode = dataGridView1[0, Row].Value.ToString(); So when you show the messagebox in the form 2 constructor, sanacode has not yet been assigned to.
There are two ways to fix this. Firstly, you can pass the value in via the constructor as per #kostas ch.'s answer, or you can override the form's OnShown event in form 2:
protected override void OnShown(EventArgs e)
{
MessageBox.Show(sanacode);
}

I wouldn't put your code
MessageBox.Show(sanacode,);
in the constructor. I would use the "Load"-Event.
If you use the "Load"-Event your MessageBox will Show, when you use
ae.Show();
Like this
private void AnalysisEdit_Load(object sender, EventArgs e)
{
MessageBox.Show(sanacode);
}

Perhaps you'd like some ideas for the various ways to pass data between forms. I have written two blog posts on the subject:
http://geek-goddess-bonnie.blogspot.com/2011/01/passing-data-between-forms.html
http://geek-goddess-bonnie.blogspot.com/2012/12/passing-data-between-forms-redux_31.html

You could temporarily add MessageBox.Show() to your setter:
// In Form2
public sanacode
{
set
{
_sanacode = value;
MessageBox.Show(_sanacode);
}
get
{
return _sanacode;
}
}

Get data from user control since Webpage

I have a simple question in asp.net.
I want to know if it is possible to get data from controls in my user control directly . I want to do it without using Session variable,Viewstate ...
EDIT: I now use the method of declaring public variables in the UC.
Here is a part of Page_load from my parent page:
this.plan_action = (UCPlan)Page.LoadControl("~/Association/UCPlan.ascx");
PlaceHolder1.Controls.Add(this.plan_action);
if (this.plan_action.Validate == true)
{
CheckBox1.Checked = true;
//String référence = Session["liste_action"].ToString();
for (int i = 0; i < this.plan_action.List1.Count; i++)
{
Label8.Text += this.plan_action.List1[i].Référence + "/";
//Label8.Text += "/";
}
}
but my variable validate stay to false.
Here is the code where I change the value of the validate variable with it declaration:
private bool validate;
public bool Validate
{
get { return validate; }
set { validate = value; }
}
protected void Button2_Click(object sender, EventArgs e)
{
//myCommand.Connection = myConnection;
//Session["liste_action"] = this.List;
this.Validate = true;
//Response.Redirect("../Risques_folder/AjouterRisque.aspx");
}
Thank you for your help,
Quentin

UPDATE due to new information
You need to learn about the sequence of events in ASP.NET.
The Load of the page happens a long time before the Click handler of Button2 in your UserControl... so the Validate property is always going to be set to false.
You have two obvious options (as I see it)...
Keep the creation of the UserControl in your Page_Load (or preferably, move it to your Page_Init, as this is normally the most appropriate place for it). Then place your check for the Validate property in a Page_PreRender.
Or, create an Event in your UserControl, Raise that event on the click of Button2, and handle the event in the Page.
ANOTHER UPDATE
For the 2nd of the two options above, in your UserControl class have the following...
public delegate void ButtonClickedDelegate(object sender, EventArgs e);
public event ButtonClickedDelegate ButtonClicked;
In the Button2_Click method of the UserControl (after setting the this.Validate = true;) call...
ButtonClickedDelegate(sender, e);
In the Page_Init of the Page, put something like...
ctrl1.ButtonClicked += new UCPlan.ButtonClickedDelegate(ctrl1_ButtonClicked);
And then have a new method called something like
void ctrl1_ButtonClicked(object sender, EventArgs e)
{
if (ctrl1.Validate)
{
...
}
}
Remember, as you control the delegate you can pass whatever information you want, including an entire class. So instead of calling the Validate property, create a new instance of the class you want, and pass that as a delegate parameter.
You can find more information on delegates and events on MSDN.
ORIGINAL ANSWER
Unless I've missed something, this is a very simple ASP.NET concept...
You can create properties and/or methods.
For example, as a property...
public string MyProperty
{
get { return "My Property Value"; }
}
Or as a method
public string MyMethod()
{
return "My Method Value";
}
If you're talking about passing the values between the UserControl and the ASP.NET Page that contains it, then in your Page, you can simply call the property or method. If your control was called (for example) myCtrl, then you can something like...
string prop = myCtrl.MyProperty;
string meth = myCtrl.MyMethod();
(On the back of the great comment from AHMED EL-HAROUNY)
If you're talking about passing the values to the client side page, then you can use the same properties / methods directly in the HTML markup. However, in this case, the properties / method can be declared as protected rather than public
For instance, to display the value...
<%=MyProperty%>
Or
<%=MyMethod()%>
Or if you're going to use the value in javascript, something like...
var myProp = "<%=MyProperty%>";

Yes That is possible, But exposing the controls in the UserControl as Public.