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variable and textbox mapping in c# without using textbox changed event

I'm trying a code which changes the TextBox values when variable mapped with it changes accordingly without using TextBox changed event. I am not finding any clue to where to start please help me.
Here is the code:
public void varChange(TextBox text)
{
String name;
name="sachin";
text.Text = name;
MessageBox.Show("" + text.Text);
}

You can "extend" TextBox :
public class MeTextBox : TextBox
{
public override string Text
{
get
{
return base.Text;
}
set
{
//base.Text = value; // use it or not .. whatever
MyTextWasChanged();
}
}
void MyTextWasChanged()
{
String name;
name="sachin";
//text.Text = name;
base.Text = name;
MessageBox.Show("" + text.Text);
}
}
If that's not what you're looking for then give some more details and I'll update this answer.

You can use a BindingSource
public partial class Form1 : Form
{
private System.Windows.Forms.BindingSource form1BindingSource;
public string BindedProp { get; set; } //Variable or property binded with TextBox
public Form1()
{
InitializeComponent();
this.form1BindingSource = new System.Windows.Forms.BindingSource(new System.ComponentModel.Container());
this.form1BindingSource.DataSource = typeof(binding.Form1);
this.textBox.DataBindings.Add(new System.Windows.Forms.Binding("Text", this.form1BindingSource, "BindedProp", true));
this.form1BindingSource.DataSource = this;
}
//add a button control to assing value code event click
private void btAssingValueProperty_Click(object sender, EventArgs e)
{
BindedProp = "Value assigned";
form1BindingSource.ResetBindings(false);
}
//add a other button control to show value code event click
private void btShowValueProperty_Click(object sender, EventArgs e)
{
MessageBox.Show(BindedProp);
}
}

Loaded an object into a listbox with 2 variables, listbox show only the name

I have a Class where there a 2 variables int ID and string name. I made a list of several objects and loaded them onto a listbox. The listbox only show the name. Is there a way to retrieve the ID from the listbox?
class Show
{
private int _Id;
private string _Naam;
private string _Genre;
public override string ToString()
{
return Naam;
}
}
from a database i make a list of objects.
private void bttn_zoek_Click(object sender, EventArgs e)
{
foreach (object a in List<show> List)
{
listbox1.Items.Add(a);
}
}
I hope this is enough

Assuming WinForms, here is a super simple example of overriding ToString() to control how the class is displayed in the ListBox, and also how to cast the selected item in the ListBox back to your class type so you can extract values from it. There are other ways to accomplish this task, but you should understand a bare bones example like this first:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
SomeClassName sc1 = new SomeClassName();
sc1.ID = 411;
sc1.Name = "Information";
listBox1.Items.Add(sc1);
SomeClassName sc2 = new SomeClassName();
sc2.ID = 911;
sc2.Name = "Emergency";
listBox1.Items.Add(sc2);
}
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
if (listBox1.SelectedIndex != -1)
{
SomeClassName sc = (SomeClassName)listBox1.Items[listBox1.SelectedIndex];
label1.Text = "ID: " + sc.ID.ToString();
label2.Text = "Name: " + sc.Name;
}
}
}
public class SomeClassName
{
public int ID;
public string Name;
public override string ToString()
{
return ID.ToString() + ": " + Name;
}
}

Posting some of your code would be nice. Have you tried listBox.items[index].ID?
Here I'm assuming that index is whatever index you're currently searching for.
You can also try listBox.SelectedItem[index].ID if you're doing something like an event.

Cannot get selectedItem to textbox

I'm trying to get listbox selected item from one form 1 to display on textbox on form 2.
So far it's working partly.
The problem is that it only gets the selectedItem that was selected at the start of the application. If the user selects a new item, it still gets the one that was selected as default.
Form 1 MainForm:
public MainForm()
{
public string GetListBoxSelectedItem()
{
if (Animallst.SelectedItem != null) //Animallst is the listbox
{
return Animallst.SelectedItem.ToString();
return string.Empty;
}
}
private void foodbtn_Click(object sender, EventArgs e)
{
FoodRegister foodForm = new FoodRegister();
foodForm.Show();
}
}
Form 2 FoodRegister:
public partial class FoodRegister : Form
{
private RecipeManager m_foodmanager = new RecipeManager();
public FoodRegister()
{
InitializeComponent();
MainForm main = new MainForm();
Nametxt.Text = main.GetListBoxSelectedItem();
//My initializations
InitializeGUI();
}
}

These two lines are not at all doing what you want them to do. You're creating an entirely new instance of MainForm, which has nothing to do with the original instance. And so GetListBoxSelectedItem() doesn't do what you want either.
MainForm main = new MainForm();
Nametxt.Text = main.GetListBoxSelectedItem();
Instead, pass a reference to the original Form into the second Form:
public FoodRegister(MainForm main)
{
InitializeComponent();
Nametxt.Text = main.GetListBoxSelectedItem();
...
And then call it like this:
FoodRegister foodForm = new FoodRegister(this);
foodForm.Show();

A couple of things to mention:
The line return string.Empty is redundant. Because of the line above it, this line becomes unreachable
In your FoodRegister for, you create a new instance of your main form. This then wipes anything that the main form was holding - i.e. Animallst.SelectedItem.ToString();
An easy way to handle this is to set the value to a static variable - that way you won't have to create a new instance of the form to access it.
Main form:
public static string GetListBoxSelectedItem()
{
if (Animallst.SelectedItem != null) //Animallst is the listbox
{
return Animallst.SelectedItem.ToString();
}
else { return string.Empty(); }
}
Food Register:
public FoodRegister()
{
InitializeComponent();
MainForm.GetListBoxSelectedItem();
//My initializations
InitializeGUI();
}

Haven't played with WinForms in awhile but here goes
In Form 2
public partial class FoodRegister : Form
{
private RecipeManager m_foodmanager = new RecipeManager();
public FoodRegister()
{
InitializeComponent();
//My initializations
InitializeGUI();
}
public void SetText(string txt)
{
Nametxt.Text = txt;
}
}
In Form 1
public MainForm()
{
private readonly FoodRegister foodForm = new FoodRegister();
private void foodbtn_Click(object sender, EventArgs e)
{
foodForm.SetText(Animallst.SelectedItem == null ? "" : Animallst.SelectedItem.ToString());
foodForm.Show();
}
}
I replaced
GetListBoxSelectedItem()
with
Animallst.SelectedItem == null ? "" : Animallst.SelectedItem.ToString()

C# - Accessing a list of Objects from one class to another

I am having this very strange problem where i am creating a list of some objects in one class then trying to access it in another class but it's coming empty in other class:
My first class where i am populating the list:
namespace dragdrop
{
struct BR
{
private string var;
public string Var
{
get { return var; }
set { var = value; }
}
private string equalsTo;
public string EqualsTo
{
get { return equalsTo; }
set { equalsTo = value; }
}
private string output;
public string Output
{
get { return output; }
set { output = value; }
}
private string els;
public string Els
{
get { return els; }
set { els = value; }
}
private string elsOutput;
public string ElsOutput
{
get { return elsOutput; }
set { elsOutput = value; }
}
}
public partial class Form1 : Form
{
//******************
private List<BR> list = new List<BR>(); //This is the list!
//******************
internal List<BR> List
{
get { return list; }
set { list = value; }
}
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
string[] vars = new string[] { "Name", "Gender", "Age", "Address", "email" };
comboBox1.DataSource = vars;
}
private void button1_Click(object sender, EventArgs e)
{
BR b = new BR();
b.Var = comboBox1.SelectedItem.ToString();
b.EqualsTo = textBox1.Text;
b.Output = textBox2.Text;
list.Add(b);
//*****************
textBox1.Text = List.Count.ToString(); //This gives the correct count value!
//*****************
//this.Close();
}
}
}
I am accessing it in second class like:
namespace dragdrop
{
public partial class Ribbon1
{
private void Ribbon1_Load(object sender, RibbonUIEventArgs e)
{
}
private void button1_Click(object sender, RibbonControlEventArgs e)
{
Form1 form = new Form1();
List<BR> l = form.List; ;
//*******************
MessageBox.Show(form.List.Count.ToString()); //This strangely gives count 0!
//*******************
}
}
}
I have even tried making everything public in first class but no matter what i do, im always getting empty list in second class.

The is no relation what-so-ever between Form1 and Ribbon1, how can one then access an instance of the other?
With this:
Form1 form = new Form1(); // new instance of Form1
List<BR> l = form.List; ; // of course the list is empty in a new instance!
you can never access values from another instance of Form1.
Since I have no idea how your classes are connected I cannot give you more advice than have a look at this good overview of OO-relationships. You have to connect them somehow for it to work, I would very much recommend composition // aggregation (same thing, different schools).

All i needed to do was make the list a static member in class one, that solved the issue of having different value when i tried to create a new instance of Form1 in Ribbon1 class.
private static List<BR> list = new List<BR>();

How to pass data between WPF forms

I need help passing data from one WPF form to another. I have a main window with two other windows that will prompt the user for information. I want to end up with all the information in the first form so that I can store the data later on. The second form must return the Reservation and Room information when you click the OK button on the second form. The third form must return the Person information when you click OK.
public partial class MainWindow : Window
{
private string message;
public MainWindow()
{
InitializeComponent();
}
protected void Exit_Click(object sender, RoutedEventArgs e)
{
Application.Current.Shutdown();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
}
protected void Create_Reservation_Click(object sender, RoutedEventArgs e)
{
Reservation PersonReservation = new Reservation();//Create a reservation instance
Room PersonRoom = new Room(); //Create an instance of a room
Person myPerson = new Person();//Create an instance of a person
CreateResRoom createReservationRoom = new CreateResRoom();//Create a instance of the CreateReservation WPF Form
createReservationRoom.Show();
Here it is supposed to set the room, reservation and person instance that I created equil to their corresponding instances in the CreateResRoom class.
I think the problem lies here, because it keeps continuing before it opens the CreateResRoom form.
PersonRoom = createReservationRoom.myRoom;
PersonReservation = createReservationRoom.myReservation;
}
}
That was my first class, the second and third will follow.
public partial class CreateResRoom : Window
{
Person myPerson;
public CreateResRoom()
{
InitializeComponent();
myReservation = new Reservation();
myRoom = new Room();
myPerson = new Person();
}
public Room myRoom
{
get;
set;
}
public Reservation myReservation
{
get;
set;
}
private void btnCancel_Click(object sender, RoutedEventArgs e)
{
this.Close();
}
private void btnOk_Click(object sender, RoutedEventArgs e)
{
myRoom.RoomBeds = txtHeadCount.Text;
myRoom.RoomNumber = 1;
myRoom.RoomPrice = 20;
myRoom.RoomType = cboRoomType.Text;
myReservation.ResEndDate = dpEnd.ToString();
myReservation.ResStartDate = dpStart.ToString();
CreateRes createReservation = new CreateRes();
createReservation.Show();
//I think the same problem lies here that is in the MainWindow.
myPerson = createReservation.myPerson;
this.Close();
}
}
And the last class follows:
public partial class CreateRes : Window
{
public Person myPerson
{
get;
set;
}
public CreateRes()
{
InitializeComponent();
myPerson = new Person();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
}
private void btnOk_Click(object sender, RoutedEventArgs e)
{
myPerson.FirstName = txtFName.Text;
myPerson.LastName = txtLName.Text;
myPerson.IdNumber = Convert.ToInt32(txtIdNumber.Text);
myPerson.PhoneNumber = Convert.ToInt32(txtPhoneNumber.Text);
myPerson.AddressCity = txtAddressCity.Text;
myPerson.AddressStreet = txtAddressStreet.Text;
myPerson.AddressProvince = txtAddressProvince.Text;
myPerson.AddressPostalCode = txtAddressPostalCode.Text;
this.Close();
}
private void btnCancel_Click(object sender, RoutedEventArgs e)
{
this.Close();
}
}

Just make a overload constructor which takes parameters of the window in which you want to retrieve.
Example:
Suppose we want a user to login from our MainWindow( i.e Login Window ) and we want to pass an int ID / string Email to our second form to retrieve data of logging user.
Than We have to first overload our second wpf form constructor. You can either make default constructor to do this or make an overload constructor for this work.
SecondForm:
public secondForm()
{
//Your Default Constructor Logic
}
public secondForm(string email_ )
{
//Your Overload Constructor Logic
}
Now in MainWindow from where we are logging and passing our EMail
MainWindow:
public void btnLogin()
{
//On Success
SecondWindow sw = new SecondWindow(txtBoxEMail.Content);
sw.Show();
}

A pattern you can use for this sort of thing is to have each form be responsible for creating the instance on ok click and then provide the object via a property get.
public partial class SomeForm: Window
{
public SomeClass MyProperty { get; private set; }
private void btnOk_Click(object sender, RoutedEventArgs e)
{
this.MyProperty = new SomeClass();
//additional setter logic here
this.Close();
}
}
Then you would access it from a parent form like this (notice the use of ShowDialog() http://msdn.microsoft.com/en-us/library/system.windows.window.showdialog(v=vs.110).aspx for easy checking of whether ok was clicked or not).
protected void Create_Reservation_Click(object sender, RoutedEventArgs e)
{
SomeClass myObj;
SomeOtherClass myOtherObj;
SomeForm myForm = new SomeForm();
if(myForm.Show().Value)
{
myObj = myForm.MyProperty;
}
SomeOtherForm myOtherForm = new SomeOtherForm();
if(myOtherForm.ShowDialog().Value)
{
myOtherObj = myOtherForm.MyOtherProp;
}
//save myObj & myOtherObj or whatever you need to do with them

Use the "normal way", here is a short overview.
First create a Data Context:
public class DC_Reservation() : INotifyPropertyChanged {
protected Reservation _PersonReservation ;
public Reservation PersonReservation {
get { return _PersonReservation ; }
set {
_PersonReservation = value;
NotifyPropertyChanged("PersonReservation ");
}
}
protected Room _PersonRoom ;
public Room PersonRoom {
get { return _PersonRoom ; }
set {
_PersonRoom = value;
NotifyPropertyChanged("PersonRoom");
}
}
protected Person _myPerson ;
public Person myPerson {
get { return _myPerson ; }
set {
_myPerson = value;
NotifyPropertyChanged("myPerson ");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void NotifyPropertyChanged( string PropertyName ) {
if ( PropertyChanged != null ) {
PropertyChanged( this, new PropertyChangedEventArgs( PropertyName ) );
}
}
}
In the MainWindows you can assign and use the dataContext :
public partial class MainWindow : Window {
DC_Reservation dataContext {
get { return DataContext as DC_Reservation; }
}
private string message;
public MainWindow() {
InitializeComponent();
DataContext = new DC_Reservation();
}
protected void Create_Reservation_Click(object sender, RoutedEventArgs e) {
dataContext.PersonReservation = new Reservation();//Create a reservation instance
dataContext.PersonRoom = new Room(); //Create an instance of a room
dataContext.myPerson = new Person();//Create an instance of a person
CreateResRoom createReservationRoom = new CreateResRoom();//Create a instance of the CreateReservation WPF Form
// I'm not sure whether the next line is required.
createReservationRoom.DataContext = DataContext;
createReservationRoom.Show();
}
}
You can assign the DataContext in the constructor, but I think the better way is to define the DataContext in the MainWindow, in the other windows you can use the DesignContext:
<Window.DataContext>
<local:DC_Reservation />
</Window.DataContext>
So you can use the same DataContext over all forms ...
With DataBindings you can bind the input to the field:
<TextBox Text="{Binding FirstName, Path=myPerson, Mode=TwoWay}" />

I found another answer that Zarathos posted Jan 16 '13 at 21:43
for a different question
Use a public static class and access it from anywhere.
public static class Globals
{
public static String s_Name = "Mike"; //Modifiable in Code
public const int32 VALUE = 10; // unmodifiable
}
Then you can use it anywhere, provided you are working on the same namespace
string name = Globals.s_Name;