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How to bind dynamically created text box?

I'm trying to create pricelist for hotel. I'm having a list of dates, and list of room types in hotel. That lists can contain random number of elements. That is created dynamically, and here is the code:
private void CreateControls() { var colIndex = 0;
var vrsteSoba = _Presenter.VrstaSobeDto.ToArray();
foreach (var bindingItem in vrsteSoba)
{
var lbl = new Label()
{
Width = LABEL_WIDTH,
Height = LABEL_HEIGHT - 5,
Left = 10,
Top = 30 + colIndex * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL),
Text = bindingItem
};
_dataPanel.Controls.Add(lbl);
colIndex++;
}
int a = 1;
foreach (var date in _Presenter.CeneTarifa)
{
int y = 0;
var panel = new Panel
{
Height = PANEL_HEIGHT * (vrsteSoba.Length-4),
Width = EDIT_BOX_WIDTH,
Left = a * (EDIT_BOX_WIDTH + SPACE_BETWEEN_CONTROL + 50),
Top = 5
};
_dataPanel.Controls.Add(panel);
var label = new Label
{
Height = EDIT_BOX_HEIGHT,
Location = new Point(0, 10),
Text = date.Datum,
Margin = new Padding(0)
};
panel.Controls.Add(label);
int index = 0;
foreach (var item in date.VrstaSobeCena)
{
var box = new TextBox();
panel.Controls.Add(box);
box.Height = EDIT_BOX_HEIGHT;
box.Width = EDIT_BOX_WIDTH;
box.Location = new Point(0, 30 + y * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL));
box.DataBindings.Add(new Binding(nameof(box.Text), date, date.Cena[index].Cena1));
y++;
index++;
}
++a;
}
_dataPanel.AutoScroll = true;
}`
Here is image of that representation.
Now I'm facing a problem of data binding. I need to bind price, two way, for each text box. And I'm stuck.
I have tried to bind it to property name, but then all boxes get same value. If I try to bind it to value via index, I'm getting error
Cannot bind to the property or column 34 on the DataSource. Parameter name: dataMember
Code below is used to fill model that is used in presenter
` private void FillCenePoTarifi() { var sobeArr = VrstaSobeDto.ToArray();
foreach (var datum in Datumi)
{
var dictionary = new Dictionary<string, decimal>();
var cene = new List<Cena>();
foreach (var item in sobeArr)
{
var tarif = _Tarife.Where(x => x.SifTarife == item).FirstOrDefault();
if (tarif != null)
_SastavTarife = HotelierServerLocal.Default.TarifaViewBlo.GetSastaveTarife(tarif.IdTarife);
//proveriti ovu logiku
var cena = _SastavTarife.Where(x => x.Cena1 != 0).Select(c => c.Cena1).FirstOrDefault();
cene.Add(new Cena { Cena1 = cena.ToString()});
dictionary.Add(item, cena);
}
var model = new CenePoTarifi
{
Datum = datum,
VrstaSobeCena = dictionary,
Cena = cene
};
CeneTarifa.Add(model);
}
}`
Finally here are classes that use as model.
` public class CenePoTarifi{
public Dictionary<string, decimal> VrstaSobeCena { get; set; } = new Dictionary<string, decimal>();
public string Datum { get; set; }
private List<Cena> _Cena;
public List<Cena> Cena
{
get => _Cena;
set
{
_Cena = value;
NotifyPropertyChanged("Cena");
}
}
public class Cena :
{
private string _Cena1;
public string Cena1
{
get => _Cena1;
set
{
_Cena = value;
NotifyPropertyChanged("Cena1");
}
}
}`
Does anyone has any suggestions?

Your question is: How to bind dynamically created text box. Here is one tested way for accomplishing that specific task.
First create some textboxes dynamically:
public MainForm()
{
InitializeComponent();
buttonRandom.Click += (sender, e) => generateRandomList();
}
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
List<TextBox> tmp = new List<TextBox>();
for (int column = 1; column < tableLayoutPanel.ColumnCount; column++)
{
for (int row = 1; row < tableLayoutPanel.RowCount; row++)
{
TextBox textBox = new TextBox { Anchor = (AnchorStyles)0xF };
tableLayoutPanel.Controls.Add(textBox, column, row);
tmp.Add(textBox);
textBox.KeyDown += onAnyTextBoxKeyDown;
}
}
_textboxes = tmp.ToArray();
// Generate first dataset
generateRandomList();
}
TextBox[] _textboxes = null;
Then, whenever a new random list is generated, clear any old text and databindings from every TextBox before creating a new data binding for it.
public static Random Rando { get; } = new Random(2);
private void generateRandomList()
{
// Clear ALL the data + bindings for ALL the textboxes.
foreach (var textbox in _textboxes)
{
textbox.Clear();
textbox.DataBindings.Clear();
}
// Generate and create new bindings
int count = Rando.Next(1, 79);
for (int i = 0; i < count; i++)
{
var textbox = _textboxes[i];
VrstaSobeCena vrstaSobeCena =
new VrstaSobeCena{ Sobe = (Sobe)tableLayoutPanel.GetRow(textbox) };
textbox.Tag = vrstaSobeCena;
textbox.DataBindings.Add(
new Binding(
nameof(TextBox.Text),
vrstaSobeCena,
nameof(VrstaSobeCena.Cena),
formattingEnabled: true,
dataSourceUpdateMode: DataSourceUpdateMode.OnPropertyChanged,
null,
"F2"
));
// TO DO
// ADD vrstaSobeCena HERE to the Dictionary<string, decimal> VrstaSobeCena
}
}
The classes shown in your code as binding sources may not bind correctly. One issue I noticed is that the property setters are failing to check whether the value has actually changed before firing the notification. Here's an example of doing that correctly. (For testing purposes I'm showing a Minimal Reproducible Sample "mock" version of a class that implements INotifyPropertyChanged.)
enum Sobe { APP4 = 1, APP5, STUDIO, SUP, APP6, STAND, STDNT, COMSTU, LUXSTU, APP4C, APP4L, APP62, APP6L }
class VrstaSobeCena : INotifyPropertyChanged
{
decimal _price = 100 + (50 * (decimal)Rando.NextDouble());
public decimal Cena
{
get => _price;
set
{
if (!Equals(_price, value))
{
_price = value;
OnPropertyChanged();
}
}
}
Sobe _sobe = 0;
public Sobe Sobe
{
get => _sobe;
set
{
if (!Equals(_sobe, value))
{
_sobe = value;
OnPropertyChanged();
}
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}
Finally, one way to test the two-way binding is to intercept the [Enter] key.
private void onAnyTextBoxKeyDown(object sender, KeyEventArgs e)
{
if ((e.KeyCode == Keys.Enter) && (sender is TextBox textbox))
{
e.SuppressKeyPress = e.Handled = true;
VrstaSobeCena vrstaSobeCena = (VrstaSobeCena)textbox.Tag;
string msg = $"Price for {vrstaSobeCena.Sobe} is {vrstaSobeCena.Cena.ToString("F2")}";
BeginInvoke((MethodInvoker)delegate {MessageBox.Show(msg); });
SelectNextControl(textbox, forward: true, tabStopOnly: true, nested: false, wrap: true);
}
}

Create a List for storing the textbox:
List<TextBox> lstTextbox = new List<TextBox>();
Create a class object that stores the values of "Date" and "room type"
public class RoomTypeDate
{
public string RoomType = "";
public string DateRange = "";
}
Immediately after you created the textbox, assigned the RoomTypeDate info to the tag, add it to lstTextbox.
foreach (var item in date.VrstaSobeCena)
{
var box = new TextBox();
panel.Controls.Add(box);
box.Height = EDIT_BOX_HEIGHT;
box.Width = EDIT_BOX_WIDTH;
box.Location = new Point(0, 30 + y * (EDIT_BOX_HEIGHT + SPACE_BETWEEN_CONTROL));
box.DataBindings.Add(new Binding(nameof(box.Text), date, date.Cena[index].Cena1));
// add the box to the list
lstTextbox.Add(box);
// mark the box with RoomType and DateRange
RoomTypeDate rtd = new RoomTypeDate();
rtd.RoomType = "APP4"; // get the room type
rtd.DateRange = "1.6 - 30.6"; // get date range
box.Tag = rtd;
y++;
index++;
}
Now, to get and set the room price:
public void SetRoomPrice(decimal price, string roomType, string dateRange)
{
foreach (var tb in lstTextBox)
{
var rtd = (RoomTypeDate)tb.Tag;
if(rtd.RoomType == roomType && rtd.DateRange == dateRange)
{
tb.Text = price.ToString();
return;
}
}
}
public decimal GetRoomPrice(string roomType, string dateRange)
{
foreach (var tb in lstTextBox)
{
var rtd = (RoomTypeDate)tb.Tag;
if(rtd.RoomType == roomType && rtd.DateRange == dateRange)
{
return Convert.ToDecimal(rt.Text);
}
}
return 0m;
}
*code untested, might contains bugs

Advanced item search in combobox C#

I wrote a program with C #
I have a combo box whose items are Binding from the database.I use AutoCompleteMode and AutoCompleteSource to search the combo box.But only when filtering does it find words whose first letter is the same as the input letter.While I need All items that contain these letters displayed.Is there a solution to this problem?

maybe this helps
// Example data
string[] data = new string[] {
"Absecon","Abstracta","Abundantia","Academia","Acadiau","Acamas",
"Ackerman","Ackley","Ackworth","Acomita","Aconcagua","Acton","Acushnet",
"Acworth","Ada","Ada","Adair","Adairs","Adair","Adak","Adalberta","Adamkrafft",
"Adams"
};
public Form1()
{
InitializeComponent();
}
private void comboBox1_TextChanged(object sender, EventArgs e)
{
HandleTextChanged();
}
// Handle Text Box that you Fill
private void HandleTextChanged()
{
var txt = comboBox1.Text;
var list = from d in data
where d.Tolower().Contains(comboBox1.Text.ToLower())
select d;
if (list.Count() > 0)
{
comboBox1.DataSource = list.ToList();
//comboBox1.SelectedIndex = 0;
var sText = comboBox1.Items[0].ToString();
comboBox1.SelectionStart = txt.Length;
comboBox1.SelectionLength = sText.Length - txt.Length;
comboBox1.DroppedDown = true;
return;
}
else
{
comboBox1.DroppedDown = false;
comboBox1.SelectionStart = txt.Length;
}
}

Changing font to DataGridView row is not working in WinForms C#

I have methods which manages datagridview object:
internal static void LoadChannelsInGrid(DataGridView dg, Label noDataLbl, string feedUrl)
{
var response = RssManager.GetRss(feedUrl);
if (response != null)
{
noDataLbl.Visible = false;
dg.Visible = true;
var items = response.OrderByDescending(s => s.PubDateUnix);
dg.DataSource = items.ToArray();
FontifyDataGrid(dg);
}
else
{
noDataLbl.Visible = true;
dg.Visible = false;
}
}
and
private static void FontifyDataGrid(DataGridView dg)
{
for (var i = 0; i < dg.Rows.Count; i++)
{
var item = dg.Rows[i].DataBoundItem as ChannelData;
if (item == null)
{
continue;
}
if (!item.IsLoaded)
{
var actualFont = new Font("Microsoft Sans Serif", 7.8f, FontStyle.Bold);
dg.Rows[i].DefaultCellStyle.Font = actualFont;
}
}
}
and I call :
LoadChannelsInGrid(dataGridView1, noDataLbl, "https://....");
Seems that rows (which model item satisfy IsLoaded value) don't have bold style, still looks regular.
Why ?

If I understood correctly, you need the font to be bold when the IsLoaded property is true.
In that case you need to update your if (!item.IsLoaded) to if (item.IsLoaded)

Looping through labels with similar name C#

I want to change the background of some labels depending on what is written on a text file:
private void Form3_Load(object sender, EventArgs e)
{
string[] words = new string[7];
StreamReader read = new StreamReader(path);
while(!read.EndOfStream)
{
string line = read.ReadLine();
words = line.Split(';');
if(words[6] == "no")
{
//-----What I have to write here---
}
}
read.Close();
}
There are over 50 labels named "lbl101","lbl102","....","lbl150"

try it:
if(words[6] == "no")
{
int count = 150;
for (int a = 1 ; a < count; a++)
{
Label currentLabel = (Label)this.Controls.Find("lbl"+a,true)[0];
//change color of currentLabel
}
}

There's the working solution:
private void Form3_Load(object sender, EventArgs e)
{
int count = 101;
string[] words = new string[7];
StreamReader read = new StreamReader(pathRooms);
while(!read.EndOfStream)
{
string line = read.ReadLine();
words = line.Split(';');
if (words[6] == "no")
{
Label currentLabel = (Label)this.Controls.Find("lbl" + count, true)[0];
currentLabel.BackColor = Color.Yellow;
}
count = count + 1;
}
read.Close();
}

You can iterate all over them using OfType<T>() method on Controls collection of form like:
if(words[6] == "no")
{
foreach(var label in this.Controls.OfType<Label>().Where(x=>x.Name.Contains("lbl")))
{
label.Text = "Some Text";
}
}
This will only work on the labels that are direct child of form, labels nested inside other user controls or nested panels will not be affected, for that you have to do it recursively.

Loop through the Controls collection of the form checking for Label objects. Then, amend accordingly as per the specified value.

1.) Create a List with all the labels.
Label lbl101 = new Label();
Label lbl102 = new Label();
...
List<Label> labels = new List<Label>()
{
lbl101,
lbl102
...
};
2.) If your words[] string is the name of the color you can write:
if(words[6] == "no")
{
System.Drawing.Color myColor = System.Drawing.ColorTranslator.FromHtml(words[..]);
foreach(Label l in Labels)
{
l.BackColor = myColor;
}
}

Get text from dynamically created WinForms textbox

I'm making a windowsform with dynamically created textboxes as u see in the method.
public void createPassengerBoxes(int numPassenger)
{
TextBox[] passengerBoxes = new TextBox[numPassenger];
for (int u = 0; u < passengerBoxes.Count(); u++)
{
passengerBoxes[u] = new TextBox();
}
int i = 0;
foreach (TextBox txt in passengerBoxes)
{
string name = "passenger" + i.ToString();
txt.Name = name;
txt.Text = name;
txt.Location = new Point(244, 32 + (i * 28));
txt.Visible = true;
this.Controls.Add(txt);
i++;
}
}
}
How do I access the text from the boxes?

While I'm not sure at what point, or based on what action, you'd like to fetch the data, here's very generic method:
private String[] GetTextBoxStrings()
{
List<String> list = new List<String>();
foreach (Control c in this.Controls)
{
if (c is TextBox)
list.Add(((TextBox)c).Text);
}
return list.ToArray();
}

Move your textbox declaration outside of the function. This makes it accessible from other functions within the class:
class MyFormsClass
{
// declare textboxes at class level
TextBox[] passengerBoxes;
public void createPassengerBoxes(int numPassenger)
{
passengerBoxes = new TextBox[numPassenger];
...
}
public void OnButtonClick(...)
{
if (passengernBoxes != null)
{
foreach (TextBox txt in passengerBoxes)
{
// do something with textboxes
}
}
}
...
}

You could also use Lambda:
var strings = Controls.OfType<TextBox>()
.Select(c => c.Text)
.ToList();
this only work if ou have no nested controls - e.g. a pannel or a group that holds some textBoxes