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Can't find a specific Control using Controls.Find()

I'm using Controls.Find() method to find a ListBox that i created dynamically. Name of those ListBoxes come from Directories that i created and named uniquely. Everytime i use this method it says the reference is null. How do i get the actual ListBox that i want?
Here is code:
public DosyaTakipAraci()
{
InitializeComponent();
string anaDizin = Properties.Settings.Default.anaDizin;
if (anaDizin == "" || anaDizin == null)
{
dizinSecici.Description = "Lütfen dosyalarınızın kaydedileceği bir dizin seçiniz.";
dizinSecici.ShowDialog();
Properties.Settings.Default.anaDizin = dizinSecici.SelectedPath + #"\";
Properties.Settings.Default.Save();
}
string[] dizinler = Directory.GetDirectories(anaDizin);
if (dizinler.Length > 0)
DizinleriYukle(dizinler);
}
This method loads all Directories
private void DizinleriYukle(string[] dizinler)
{
for (int i = 0; i < dizinler.GetLength(0); i++)
{
DirectoryInfo dizin = new DirectoryInfo(dizinler[i]);
DizinYukleyici(dizin.Name);
}
}
This method is belongs to Directory icon that is created for each Directory
private void DizinSimge_DragDrop(object sender, DragEventArgs e)
{
string[] dosyalar = (string[])e.Data.GetData(DataFormats.FileDrop);
PictureBox simge = (PictureBox)sender;
string dizinAdi = simge.Name;
string anaDizin = Properties.Settings.Default.anaDizin;
foreach (string dosya in dosyalar)
{
string dosyaAdi = Path.GetFileName(dosya);
if (File.Exists($#"{anaDizin}{dizinAdi}\{dosyaAdi}"))
return;
File.Copy(dosya, $#"{anaDizin}{dizinAdi}\{dosyaAdi}", true);
DosyaYukleyici(Panel.Controls.Find(dizinAdi, true).FirstOrDefault() as ListBox);
}
}
This method loads the Directory and creates Controls related to the Directory
private void DizinYukleyici(string dizinAdi)
{
#region Kontrol tanımları
PictureBox dizinSimge = new PictureBox
{
Name = dizinAdi,
Image = Properties.Resources.folder,
Size = new Size(32, 32),
Location = new Point(this.X, this.Y),
AllowDrop = true
};
TextBox dizinBaslik = new TextBox
{
Name = dizinAdi,
Text = dizinAdi,
Location = new Point(this.X + dizinSimge.Width + 5, this.Y + 8),
Font = new Font("Segou UI", 8.25f),
BackColor = this.BackColor,
BorderStyle = BorderStyle.None,
ReadOnly = true
};
ListBox Dosyalar = new ListBox
{
Name = dizinAdi,
Text = null,
Location = new Point(this.X, this.Y + dizinSimge.Height + 5),
BorderStyle = BorderStyle.None,
BackColor = this.BackColor,
Width = dizinSimge.Width + dizinBaslik.Width + 5
};
#endregion
#region Olaylar
dizinSimge.DragEnter += new DragEventHandler(DizinSimge_DragEnter);
dizinSimge.DragDrop += new DragEventHandler(DizinSimge_DragDrop);
dizinBaslik.DoubleClick += new EventHandler(Baslik_DoubleClick);
dizinBaslik.KeyPress += new KeyPressEventHandler(Baslik_Press);
Dosyalar.DragEnter += new DragEventHandler(DizinSimge_DragEnter);
Dosyalar.DragDrop += new DragEventHandler(Dosyalar_DragDrop);
#endregion
Panel.Controls.Add(dizinSimge);
Panel.Controls.Add(dizinBaslik);
Panel.Controls.Add(Dosyalar);
DosyaYukleyici(Dosyalar);
this.X += (short)(dizinSimge.Width + dizinBaslik.Width + 5);
}
This method Loads files of a Directory and adds them to related ListBox
private void DosyaYukleyici(ListBox Liste)
{
string dizinAdi = Liste.Name;
Liste.Items.Clear();
string anaDizin = Properties.Settings.Default.anaDizin;
string dizin = Path.Combine(anaDizin, dizinAdi);
string[] dosyalar = Directory.GetFiles(dizin);
foreach (string dosya in dosyalar)
{
Liste.Items.Add(Path.GetFileName(dosya));
}
}

You give the PictureBox, the TextBox and the ListBox the same name dizinAdi. Now when you search a ListBox, you may find a PictureBox or a TextBox first. Then you try to cast it with as ListBox which yields null if it is not the ListBox.
Filter the by type:
Panel.Controls.Find(dizinAdi, true).OfType<ListBox>().FirstOrDefault()
alternatively, you could give different names to different controls like
"lst" + dizinAdi
"txt" + dizinAdi
"pic" + dizinAdi
or
dizinAdi + "ListBox"
dizinAdi + "TextBox"
dizinAdi + "PictureBox"

How to access and change the property of a label that I created dynamically

I wanna change the Text properties of Label using Buttons just like in hangman; but after I created the Label, I became confused when I try to access the specific Label
// creating label
for (int i = 0; i < numericUpDown1.Value; i++)
{
Label l = new Label();
l.Text = "_";
l.Width = 20;
l.Height = 25;
l.Left = i * 20 + 510;
l.Top = 20;
l.BackColor = Color.Transparent;
groupBox2.Controls.Add(l);
}
// function to change the label text
// if I clicked the button
// the first label text will be changed to the text in the button i clicked
private void B_Click(object sender, EventArgs e)
{
var thsBtn = (Button)sender;
bool benar = false;
if (benar == false)
{
thsBtn.Text = " ";
thsBtn.Enabled = false;
}
else
{
thsBtn.Enabled = false;
}
}

You can organize created Labels into a collection, say, List<Label>:
private List<Label> m_CreatedLabels = new List<Label>();
...
// Remove all previous labels
foreach (Label lbl in m_CreatedLabels)
lbl.Dispose();
m_CreatedLabels.Clear();
// Create new ones
for (int i = 0; i < numericUpDown1.Value; i++) {
m_CreatedLabels.Add(new Label() {
Text = "_",
Width = 20,
Height = 25,
Left = i * 20 + 510,
Top = 20,
BackColor = Color.Transparent,
Parent = groupBox2
});
}
Now you have m_CreatedLabels collection to work with created Labels, e.g.
private void B_Click(object sender, EventArgs e) {
var thsBtn = sender as Button;
// you may want to add a condition into FirstOrDefault(), e.g.
// .FirstOrDefault(lbl => lbl.Text == "_")
// - first label with "_" Text
Label lblToProcess = m_CreatedLabels
.FirstOrDefault();
if (null != lblToProcess)
lblToProcess.Text = thsBtn.Text;
thsBtn.Enabled = false;
}

One option here is to give your dynamically created Label instances a Name. From there, you should be able to use ControlCollection.Find to find your Label instances by name.
private void CreateLabels()
{
for (int i = 0; i < numericUpDown1.Value; i++)
{
Label l = new Label();
l.Name = $"DynamicLabel{i}";
l.Text = "_";
l.Width = 20;
l.Height = 25;
l.Left = i * 20 + 510;
l.Top = 20;
l.BackColor = Color.Transparent;
groupBox2.Controls.Add(l);
}
}
private void DoSomethingWithADynamicLabel(int dynamicLabelIndex)
{
Label l = groupBox2.Controls.Find($"DynamicLabel{i}", true).FirstOrDefault() as Label;
if (l is null)
{
// Couldn't find the label...
return;
}
// Do something with l
}
When creating the Label instances inside CreateLabels, I'm simply appending the for loop's counter to the string "DynamicLabel". This gives you a bunch of Labels with names like "DynamicLabel0", "DynamicLable1", "DynamicLabel2", etc...
Then in DoSomethingWithADynamicLabel, assuming you have the index of the Label you want to deal with, you can use groupBox2.Controls.Find to actually find the Label you're interested in. ControlCollection.Find returns Control[], so calling FirstOrDefault will take the first item from the array or null if no Control with the given name exists.

Dynamic button, textbox and picturebox creation

Here I am doing a project where questions are presented in images. When the project loads, "start exam" button will be present in the screen. After pressing the button, it should create a picturebox, a textbox and a button for each image from specified path. Then users has to enter the answer in a textbox which is created dynamically. After the dynamic submit button is clicked for every image, the textbox values have to be stored in the listbox. I don't know how get the values from textbox. Can anyone help me out from this?
Here is my code:
PictureBox[] pics = new PictureBox[100];
TextBox[] txts = new TextBox[100];
Button[] butns = new Button[100];
FlowLayoutPanel[] flws = new FlowLayoutPanel[100];
private void button1_Click( Object sender , EventArgs e)
{
for (int i = 0; i < listBox1.Items.Count; i++)
{
flws[i] = new FlowLayoutPanel();
flws[i].Name = "flw" + i;
flws[i].Location = new Point(3,brh);
flws[i].Size = new Size(317,122);
flws[i].BackColor = Color.DarkCyan;
flws[i].BorderStyle = BorderStyle.Fixed3D;
pics[i] = new PictureBox();
pics[i].Location = new Point(953, 95 + brh);
pics[i].Name = "pic" + i;
pics[i].Size = new Size(300, 75);
pics[i].ImageLocation = "C:/" + listBox1.Items[i];
flws[i].Controls.Add(pics[i]);
txts[i] = new TextBox();
txts[i].Name = "txt" + i;
txts[i].Location = new Point(953, 186 + brh);
flws[i].Controls.Add(txts[i]);
butns[i] = new Button();
butns[i].Click += new EventHandler(butns_Click);
butns[i].Text = "submit";
butns[i].Name = "but" + i;
butns[i].Location = new Point(1100, 186 + brh);
flws[i].Controls.Add(butns[i]);
flowLayoutPanel1.Controls.Add(flws[i]);
brh += 130;
}
}
private void butns_Click(object sender, EventArgs e)
{
Button butns = sender as Button;
TextBox txts = sender as TextBox;
listBox2.Items.Add("text values " + txts.Text.ToString());
}

I would create a usercontrol to combine the controls.
Search for "custom usercontrol c#"
Regards.

Try this...
private void butns_Click(object sender, EventArgs e)
{
Button butns = sender as Button;
string btnName = butns.Name;
string Id = btnName.Substring(3);
string txtName = "txt" + Id;
listBox2.Items.Add("text values " + GetValue(txtName));
}
private string GetValue(string name)
{
TextBox txt = new TextBox();
txt.Name = name;
foreach (Control ctl in this.Controls)
{
if (ctl is FlowLayoutPanel)
{
foreach (Control i in ctl.Controls)
{
if (((TextBox)i).Name == txt.Name)
{
txt = (TextBox)i;
return txt.Text;
}
}
}
}
return txt.Text;
}

storing multiple controls and update radio button values?

What am doing here is; making a UI to update values visually, will add more support for other types too. Possibly all types.
updateIcons this function is called everytime the controller is loaded, and has new values,names everytime.
countControls to keep track of controllers, so if can update values on clicks.
myP is the object that holds the values taken at runtime, user shuffles values by pressing tab from another screen
created radiobuttons groupboxes to allow radiobutton group to be managed.
properties all belong to one object. each property has few possible values like in my example, the enums.
now am kinda lost, not sure how to best do this, as now my rb_CheckedChanged is returning some kind of mess.
How do i do this the right way ? all together, i feel its somewhat the right approach At least.
I thought of making a dictionary of ? to use it at the checked event. not exactly sure how
private void updateIcons(List<Props> prop) {
countControls++;
locationY = 10;
int gbHeight;
foreach (var p in prop) {
radioButtonY = 10;
IType pType = p.Type;
if (pType is Enum) {
var myP = new MyProp(p, this);
GroupBox gb = new GroupBox();
gb.Location = new Point(nextLocationX,locationY);
nextLocationX += rbWidth+10;
gb.Name = "groupBox" + countControls;
gb.Text = "smthn";
var TypesArray = set here;
gbHeight = TypesArray.Length;
foreach (var type in TypesArray) {
getimagesPath(TypesArray);
RadioButton rb = new RadioButton();
rb.Appearance = Appearance.Button;
rb.Width = rbWidth;
rb.Height = rbHeight;
rb.Name = type.Name + countControls;
rb.Text = type.Name;
string path = imagePaths[type.Name];
Bitmap rbImage = new Bitmap(path);
rb.BackgroundImage = rbImage;
countControls++;
rb.Location = new Point(radioButtonX, radioButtonY);
if (myP.Value != null && type.Name.SafeEquals(myP.Value.ToString())) {
rb.Checked = true;
}
radioButtonY += rbHeight;
gb.Controls.Add(rb);
rb.CheckedChanged += rb_CheckedChanged;
}
gb.Height = rbHeight * gbHeight + 20;
gb.Width = rbWidth + 10;
Controls.Add(gb);
}
}
}
void rb_CheckedChanged(object sender, EventArgs e) {
RadioButton rb = (RadioButton)sender;
Control control = (Control)sender;
if (rb.Checked) {
MessageBox.Show("You have just checked: " + rb.Text);
MessageBox.Show("You have just called Controller: " + control.Name);
var t = PropSeq;
}
else {
MessageBox.Show("you have just unchecked: " + rb.Text);
MessageBox.Show("You have just called Controller: " + control.Name);
}
}

I think your code might be a little messed up and not the easiest to read. It looks plain invalid with not all closing braces present? Try the code below which will create two group boxes, each with five radio buttons. This should help you achieve what you are trying to do (full listing for a basic Form):
using System;
using System.Drawing;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
CreateButton();
}
private void CreateButton()
{
// Add two group boxes
for (int groupCount = 1; groupCount < 3; groupCount++)
{
var groupBox = new GroupBox();
groupBox.Location = new Point(220 * (groupCount - 1), 10);
groupBox.Name = string.Format("groupBox{0}", groupCount);
groupBox.Text = string.Format("Group Box {0}", groupCount);
// Add some radio buttons to each
for (int buttonCount = 1; buttonCount < 6; buttonCount++)
{
var radioButton = new RadioButton();
radioButton.Width = 150;
radioButton.Location = new Point(10, 30 * buttonCount);
radioButton.Appearance = Appearance.Button;
radioButton.Name = string.Format("radioButton{0}", buttonCount);
radioButton.Text = string.Format("Dynamic Radio Button {0} - {1}", groupCount, buttonCount);
radioButton.CheckedChanged += radioButton_CheckedChanged;
// Add radio button to the group box
groupBox.Controls.Add(radioButton);
groupBox.Height += 20;
}
// Add group box to form
Controls.Add(groupBox);
}
}
private void radioButton_CheckedChanged(object sender, EventArgs e)
{
// Get button and only show the selected (not now de-selected item)
var radioButton = (RadioButton)sender;
if (radioButton.Checked)
{
MessageBox.Show("You have just checked: " + radioButton.Text);
}
}
}
}

C# deleting dynamic textboxes by checkboxing

I am writing a code in C# I have 2 Forms and the code creates textboxes and corresponding checkboxes dynamically. The code I wrote creates dynamic textboxes and checkboxes successfully. However, I am not able to delete the row of textboxes in a selected checkbox line.
public void CreateTextBox(int i, StringReader sr)
{
ProductForm form2 = new ProductForm();
_cb = new CheckBox[i];
form2.Visible = true;
form2.Activate();
int x = 10;
int y = 30;
int width = 100;
int height = 20;
for (int n = 0; n < i; n++)
{
String line = sr.ReadLine();
String[] line_ = line.Split(new char[] {'\t'});
String cbName = "chkBox_" + n.ToString();
_cb[n] = new CheckBox();
_cb[n].Name = cbName;
_cb[n].Location = new Point(2, y);
_cb[n].Checked = false;
form2.Controls.Add(_cb[n]);
if (line.Length > 3)
{
for (int row = 0; row < 4; row++)
{
String name = "txtBox_" + row.ToString();
TextBox tb = new TextBox();
tb.Name = name;
tb.Text = line_[row].ToString();
tb.Location = new Point(x, y);
tb.Height = height;
if (row == 1)
{
tb.Width = width * row;
}
if (row == 3)
{
tb.Width = width * 5;
}
else
{
tb.Width = width - 20;
}
x += 10 + width;
form2.Controls.Add(tb);
}
}
x = 10;
y += 25;
}
}
private void DeleteTextBoxButton_Click(object sender, EventArgs e)
{
//Here should I add a code in order to delete dynamically created
//textboxes by clicking checkbox and button
}
}

Not sure of your question. But if I am right, this could do the trick.
SOLUTION1: While creating all the controls, add them to a List<Controls>. When you are checking the checkbox to delete the row, get the name of the checkbox, search it in the List<Controls>. So this way can get the index of the row of the checkbox clicked. Now delete the controls of that rows.
SOLUTION2: Create your controls in a TablelayoutPanel and everything will be easy.
EDIT
Copy paste everything in the form1, se btn_click as a event handler for a button. Let the size of the form a bit big. Everything should work fine now. If not working, let me know.
class MyControl
{
public TextBox txt1 { get; set; }
public TextBox txt2 { get; set; }
public TextBox txt3 { get; set; }
public TextBox txt4 { get; set; }
public CheckBox cb { get; set; }
public MyControl(TextBox txt1, TextBox txt2, TextBox txt3, TextBox txt4, CheckBox cb)
{
this.txt1 = txt1;
this.txt2 = txt2;
this.txt3 = txt3;
this.txt4 = txt4;
this.cb = cb;
}
}
List<MyControl> list = new List<MyControl>();
public int x = 50, n = 1;
TextBox txtTemp, txt1, txt2, txt3, txt4;
CheckBox cbTemp;
private void btn_Click(object sender, EventArgs e)
{
txtTemp = new TextBox();
txtTemp.Location = new System.Drawing.Point(10, x);
txtTemp.Name = "txt1_" + n;
txt1 = txtTemp;
txtTemp = new TextBox();
txtTemp.Location = new System.Drawing.Point(120, x);
txtTemp.Name = "txt2_" + n;
txt2 = txtTemp;
txtTemp = new TextBox();
txtTemp.Location = new System.Drawing.Point(230, x);
txtTemp.Name = "txt3_" + n;
txt3 = txtTemp;
txtTemp = new TextBox();
txtTemp.Location = new System.Drawing.Point(350, x);
txtTemp.Name = "txt4_" + n;
txt4 = txtTemp;
cbTemp = new CheckBox();
cbTemp.Name = "cb1_" + n;
cbTemp.Enter += new EventHandler(cbTemp_Enter);
cbTemp.Location = new System.Drawing.Point(490, x);
this.Controls.Add(txt1);
this.Controls.Add(txt2);
this.Controls.Add(txt3);
this.Controls.Add(txt4);
this.Controls.Add(cbTemp);
list.Add(new MyControl(txt1, txt2, txt3, txt4, cbTemp));
x += 40;
n++;
}
void cbTemp_Enter(object sender, EventArgs e)
{
if ((MessageBox.Show("Are you Sure?", "Warning", MessageBoxButtons.YesNo)) == DialogResult.No)
return;
CheckBox cbMain = (CheckBox)sender;
int index = Search(cbMain);
this.Controls.Remove(list[index].txt1);
this.Controls.Remove(list[index].txt2);
this.Controls.Remove(list[index].txt3);
this.Controls.Remove(list[index].txt4);
this.Controls.Remove(list[index].cb);
}
private int Search(CheckBox cbMain)
{
int temp = 0;
foreach (MyControl item in list)
{
if(cbMain.Name == item.cb.Name)
temp = list.IndexOf(item);
}
return temp;
}

For WinForms, I recommend putting the generated TextBoxes into the Tag field of the CheckBox. Then keep a managed list of all CheckBoxes. Once they click the delete button, iterate through the collection of CheckBoxes. If their state is checked, pull the TextBox out of the Tag field, remove it from the form collection, then delete it.
NOTE: This code is untested but should work in principle.
UPDATE: Reading your latest comment, instead of storing a single TextBox in the Tag, just create another List of them and store the entire list in the tag. Then iterate through those in the delete method.
private List<CheckBox> _checkboxes = new List<CheckBox>();
public void CreateTextBox( int i, StringReader r )
{
// ... do your stuff here
_cb[n].Tag = tb;
// ... finish up
_checkboxes.Add( _cb[n] );
}
public void DeleteTextBoxButton_Click( object sender, EventArgs e )
{
foreach( var cb in _checkboxes )
{
if( cb.Checked )
{
TextBox tb = cb.Tag as TextBox;
if( tb != null )
{
form2.Controls.Remove( tb );
}
}
}
}