Ok so I am trying to pass a boolean from my Login form to my Home form, normally this would be fine for me and I would just use a property. However I thought I could use a similar method this time but I am implementing the singleton factory on the forms.
Here is the Login code relevant to this:
The AdminAccess property gets set fine and I have checked the value is correct.
private bool adminAccess;
public bool AdminAccess
{
get { return adminAccess; }
private set { adminAccess = value; }
}
private void btnLogin_Click(object sender, EventArgs e)
{
//Some Code Does Stuff
OpenHome();
}
private void OpenHome()
{
HomeForm CreateHomeForm = HomeForm.HomeUI;
CreateHomeForm.StartupHome = this;
//Trying to set the property.
CreateHomeForm.AdminPermissions= this.AdminAccess;
CreateHomeForm.Show();
this.Hide();
}
Here is the relevant code from the Home form:
public HomeForm()
{
InitializeComponent();
//just to check what is in the property quickly
textBox1.Text = AdminPermissions.ToString();
}
private bool adminPermissions;
public bool AdminPermissions
{
private get { return adminPermissions; }
set { adminPermissions = value; }
}
public Form StartupHome
{
set;
get;
}
private static HomeForm homeUI;
public static HomeForm HomeUI
{
get
{
if (homeUI == null || homeUI.IsDisposed)
{
homeUI = new HomeForm();
}
return homeUI;
}
}
The value gets reset when the HomeUI if loop runs as a new instance of the form is created. I can't seem to think how to modify this to get a working solution. As you can tell I am fairly amateur so I'm just looking for a quick and clean solution to this :)
Thank you very much for your time in advance!
You assign the value in the constructor, BEFORE the AdminPermissions property is actually set. Change your code like this
public class HomeForm
{
public HomeForm()
{
InitializeComponent();
}
private bool adminPermissions;
public bool AdminPermissions
{
get { return adminPermissions; }
set {
adminPermissions = value;
textBox1.Text = value.ToString();
}
}
...
}
Try setting the textBox1.Text value in one of the Form events. Try Loaded first, then Activated. You're resetting it to false every time in your constructor!
Related
I want to get value of TextBox in Form1, to another class.
I try to make a set and get, but I can't do this, because VS shows me error about ambiguity in code.
public partial class Form1 : Form
{
private TextBox _textBox1;
public Form1()
{
this._textBox1 = textBox1;
InitializeComponent();
}
public string _textBox1
{
get { return _textBox1.Text; }
set { _textBox1.Text = value; }
}
}
How to make this correct? My control is private.
You have one field and one property in you class with the same name, change the name of the property, for instance to
public string FormTextBox1
{
get { return _textBox1.Text; }
set { _textBox1.Text = value; }
}
as naming standard the public properties must be Pascal Case notation
Capitalization Conventions
You can pass textBox1.Text to a variable, and make a getter/setter for it.
Like this:
public class A : Form1
{
// assuming it's a string. If it's not, change the type
// for the getter method below accordingly
private string textBoxValue;
// at some point, you'll have to make this line below:
textBoxValue = textBox1.Value;
public string GetTextBoxValue()
{
return textBoxValue;
}
}
public class B
{
A aReference = new A();
// you can get the value you want by doing
// aReference.GetTextBoxValue();
}
public void yourFormLoadMethod()
{
//this instantiates a new object of your class
nameOfYourClass newYourObject = new nameOfYourClass(//put any params you need here);
txtNameOfYourTextBox.DataBindings.Add("Enabled", newLTDObjectBenInt, "YourTextBoxEnabled", true, DataSourceUpdateMode.OnPropertyChanged);
txtNameOfYourTextBox.DataBindings.Add("Value", newLTDObjectBenInt, "YourTextBoxEntered", true, DataSourceUpdateMode.OnPropertyChanged);
txtNameOfYourTextBox.DataBindings.Add("Visible", newLTDObjectBenInt, "YourTextBoxVisible", true, DataSourceUpdateMode.OnPropertyChanged);
}
public class nameOfYourClass
{
//constructor
public nameOfYourClass(//same params here from the Load method)
{
//place any logic that you need here to load your class properly
//this sets default values for Enable, Visible and the text
//you use these fields to manipulate your field as you wish
yourTextBoxVisible = true;
yourTextBoxEnabled = true;
yourTextBoxEntered = "this is the default text in my textbox";
}
private bool yourTextBoxEnabled;
public bool YourTextBoxEnabled
{
get
{
return yourTextBoxEnabled;
}
set
{
yourTextBoxEnabled = value;
}
}
private bool yourTextBoxVisible;
public bool YourTextBoxVisible
{
get
{
return yourTextBoxVisible;
}
set
{
yourTextBoxVisible = value;
}
}
private string yourTextBoxEntered;
public string YourTextBoxEntered
{
get
{
return yourTextBoxEntered;
}
set
{
yourTextBoxEntered = value;
}
}
}
I have found many answered questions on here explaining how to do this when the objects are created as part of the data source but my list box is just displaying "SharePointXMLBuilder.Farm" (Namespace.class) and not the selected DisplayName?
I dont know what I am doing wrong can anyone help please.
I have a list box with a data source as a databinding control and I am adding my created objects(Farm) to the databinding(farmListBindingSource) which all works fine, I just cant get the list to show the property I want it to.
Form: (loads another form takes input and returns to create object from Farm class)
private void CreateNewFarm_Click(object sender, EventArgs e)
{
FarmInput input = new FarmInput();
input.ShowDialog();
Farm nFarm = new Farm();
nFarm.location = input.inputLocation.ToString();
nFarm.identifier = input.inputType.ToString();
nFarm.environment = input.inputEnvironment.ToString();
this.farmListBindingSource.Add(nFarm);
this.testReturnTextBox.Text = nFarm.friendlyName;
}
private void MainForm_Load(object sender, EventArgs e)
{
this.FarmListBox.DisplayMember = "friendlyName";
this.testReturnTextBox.Text = "Form Loaded....";
}
Class:
namespace SharePointXMLBuilder
{
class Farm
{
private string farmLocation;
private string farmIdentifier;
private string farmEnvironment;
private string farmFriendlyName;
//private List<Server> farmServers;
//properties
public string friendlyName
{
get { return farmFriendlyName; }
set { farmFriendlyName = value; }
}
public string location
{
get { return farmLocation;}
set { farmLocation = value; this.buildFriendlyName(); }
}
public string identifier
{
get { return farmIdentifier; }
set { farmIdentifier = value; this.buildFriendlyName(); }
}
public string environment
{
get { return farmEnvironment; }
set { farmEnvironment = value; this.buildFriendlyName(); }
}
//constructor
public Farm()
{
}
//methods
public void AddServer(string s)
{
Server nServer = new Server(s);
// farmServers.Add(nServer);
}
public void buildFriendlyName()
{
this.friendlyName = this.location + " " + this.identifier + " " + this.environment;
}
}
}
Maybe you are not calling this function: buildFriendlyName() for each object in the list prior to binding?
In your buildfriendlyname() method set your private string farmFriendlyName insted of setting the property value friendlyname
Ok, so I tried to manually add DisplayMember in the designer and it wouldn't hold the value, as soon as I removed the DataSource it allowed DisplayMember to be populated so I changed the CreateNewFarm_Click to add the object to farmListBox.Items and when I re-ran the code it was fine.
It appears that you cannot use DisplayMember if you are pulling the objects from a DataSource.
I'm trying to get a new form (FormAlbum) to open when I click buttonOpenAlbum and have an item selected in the AlbumListBox.
If I just have this in buttonOpenAlbum_Click:
private void buttonOpenAlbum_Click(object sender, EventArgs e)
{
FormAlbum MusicForm = new FormAlbum(this);
MusicForm.ShowDialog();
}
The new from opens without error. However, as soon as I mention "AlbumListBox.SelectedItem" (as in the code belowin Form FormMain), I get a "StackOverflowException was unhandled" at:
public ListBox AlbumListBox
{
get
{ // <-This bracket here is where the error highlights
I don't understand why I'm getting this error, only that it must have something to do with AlbumListBox. What am I doing wrong? Any help is appreciated, thank you.
Form FormMain:
public FormMain()
{
InitializeComponent();
}
private void buttonAddAlbum_Click(object sender, EventArgs e)
{
FormAlbumAC addAlbumForm = new FormAlbumAC(this);
addAlbumForm.ShowDialog();
}
private void buttonOpenAlbum_Click(object sender, EventArgs e)
{
if (AlbumListBox.SelectedItem != null)
{
MessageBox.Show(AlbumListBox.SelectedItem.ToString());
FormAlbum MusicForm = new FormAlbum(this);
MusicForm.ShowDialog();
}
else
{
MessageBox.Show("You need to select an album from the list to open.");
}
}
public static class PublicVars
{
public static List<Album> AlbumList { get; set; }
static PublicVars()
{
AlbumList = new List<Album>(MAX_ALBUMS);
}
}
public ListBox AlbumListBox
{
get
{
return AlbumListBox;
}
}
Look at your property implementation:
public ListBox AlbumListBox
{
get
{
return AlbumListBox;
}
}
It's just calling itself, recursively. It may be easier to see that if we convert it to a method:
public ListBox GetAlbumListBox()
{
return GetAlbumListBox();
}
That's why you've got an overflow. It's not clear what you meant it to do... where did you expect the value to come from? You probably need a variable to back the property. What did you expect to set the value returned?
I'd also strongly discourage the design of the PublicVars class. Aside from the naming, you're basically using global variables - not a good idea. Work out which classes need access to the data, and how to get that data to them appropriately.
I have the a class in my application. It has been bound to winform textbox controls. But the textbox which is bound to BookingNo property, always shows zero (0). But i want the textbox keep empty. Is there any way to do it? Here is my code snippet.
public class Booking
{
private int pBookingNo;
private string pCustomerName;
private string pAddress;
public int BookingNo
{
get { return pBookingNo; }
set
{
if (!value.Equals(pBookingNo))
{
pBookingNo = value;
}
}
}
public string CustomerName
{
get { return pCustomerName; }
set
{
if (!value.Equals(pCustomerName))
{
pCustomerName = value;
}
}
}
public Booking() { }
}
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
AddDataBindings();
}
private void AddDataBindings()
{
bsBooking.DataSource = typeof(Booking);
txtBookingNo.DataBindings.Add("Text", bsBooking, "BookingNo", true, DataSourceUpdateMode.OnPropertyChanged, null, "G", GlobalVariables.CurrentCultureInfo);
txtCustomerName.DataBindings.Add("Text", bsBooking, "CustomerName");
}
}
The default value of an Integer is 0, so you have to wrap it into some other object, which supports values other than 0, like
public int? BookingNo { get; set; }
You can use Nullable Type
public int? pBookingNo
{
get;
set;
}
Link : http://msdn.microsoft.com/fr-fr/library/1t3y8s4s(v=vs.80).aspx
You could use custom formatting for the binding by adding a handler to the Format event (http://msdn.microsoft.com/en-us/library/system.windows.forms.binding.format.aspx) and return an empty string when the value is zero. But you wouldn't be able to tell whether the value is actually zero or it just hasn't been set already, in which case using the int? approach suggested by #Grumbler85 is better.
what´s about:
textBox1.BindingContextChanged += new EventHandler(BindingContext_Changed);
private void BindingContext_Changed(object sender, EventArgs e)
{
TextBox txtBox = (TextBox)sender;
if (txtBox.Text == "0"){
txtBox.Text = "";
}
}
don´t know if it works, just an idea.
I have a second window which opens when a certain staffname is searched for, this window prompts you to choose between the 2 staff members with the same name. The window then needs to return a value to the parent window to populate a datatemplate with relating data from the xml file.
I've tried to create a string which will be updated with a value depending on which button is clicked, this string can then be returned to the calling method on the first window and populate binding data in the Linq to Xml query.
But when it runs it causes a stackoverflow exception and that it could be an infinite loop. I'm not sure enough about c# to know what to change.
public partial class Choice : Window
{
private string StaffChoice;
public Choice()
{
InitializeComponent();
}
public string staffChoice
{
get { return this.StaffChoice; }
set { staffChoice = StaffChoice; }
}
private void btnMRG_Click(object sender, RoutedEventArgs e)
{
StaffChoice = "MRG";
this.Close();
}
private void btnRPG_Click(object sender, RoutedEventArgs e)
{
StaffChoice = "RPG";
this.Close();
}
}
Any help or suggestions would be great!
Thanks in advance!
Firstly, your naming conventions are wrong - the field should be called staffChoice and the property should be called StaffChoice. Please read the .NET naming conventions for more information. However, now look at your property closely:
public string staffChoice
{
get { return this.StaffChoice; }
set { staffChoice = StaffChoice; }
}
What do you think the setter does? There are two problems with it:
It ignores the value that you're trying to set it to.
It calls itself recursively.
You could fix this by keeping the manually-declared field, fixing the naming conventions, and changing the property to set the variable to value like this:
private string staffChoice;
public string StaffChoice
{
get { return staffChoice; }
set { staffChoice = value; }
}
However, it would be simpler to use an automatically implemented property:
public string StaffChoice { get; set; }
This will create the backing field and the getter/setter for you automatically.
The simplest way is to declare a property like this...
public string StaffChoice { get; set; }
your problem is you are basically calling the property setter from within the same setter - thus you have a recursive loop. You could change your code like this to make it work...
private string StaffChoice;
public string staffChoice
{
get { return this.StaffChoice; }
set { StaffChoice = value; }
}
Your setter isn't right, you are assigning a value to itself (causing the infinite loop) and not using value.
You should change your code to this, your naming convention looked backwards so I corrected it, hope you don't mind:
private string staffChoice;
public Choice()
{
InitializeComponent();
}
public string StaffChoice
{
get { return staffChoice; }
set { staffChoice = value; }
}
private void btnMRG_Click(object sender, RoutedEventArgs e)
{
staffChoice = "MRG";
this.Close();
}
private void btnRPG_Click(object sender, RoutedEventArgs e)
{
staffChoice = "RPG";
this.Close();
}
Your property should be:
public string staffChoice
{
get { return this.StaffChoice; }
set { this.StaffChoice = value; }
}
In your code you are calling the setter again in the setter - hence the infinite recursion.
However, as you are not doing anything special in the setter (like notifying the UI that the property has changed you could simply have:
public string staffChoice { get; set; }
This "auto property" is a little cleaner.
(BTW: the normal practice is to have the back variable starting with a lower case letter and the public property starting with an upper case one. However, if you are consistent in your application it doesn't really matter.)