Develop Reference

Delete all dynamically created PictureBoxes with the same parent in c#

I am writing a windows forms application in C# in which i am dynamically creating TextBoxes and PictureBoxes with a Panel as the parent:
PictureBox pb = new PictureBox();
pb.Parent = MainPanel;
pb.Name = "pb" + "r" + NumberInRow + "c" + NumberInColumn+ "bi" + buildIndex;
pb.Location = new Point(30 * NumberInRow + 192 * (NumberInRow - 1), 50 * NumberInColumn + 273 * (NumberInColumn - 1));
pb.ImageLocation = ThumbLinks[i];
TextBox tb = new TextBox();
tb.Parent = MainPanel;
tb.Name = "tb" + "r" + NumberInRow + "c" + NumberInColumn + "bi" + buildIndex;
tb.Location = new Point(pb.Location.X - 4, pb.Location.Y + pb.Size.Height + 5);
tb.Text = GalleryNames[i];
I am trying to delete them with this:
foreach (PictureBox pb in MainPanel.Controls)
{
MainPanel.Controls.Remove(pb);
}
foreach (TextBox tb in MainPanel.Controls)
{
MainPanel.Controls.Remove(tb);
}
This only seems to work once though.
Visual Studio tells me that it can't convert System.Windows.Forms.TextBox into System.Windows.Forms.PictureBox.
Is there any way to delete the PictureBoxes and TextBoxes differently?
I've read about something like MainPanel.Children.Remove(); but it doesn't seem to exist or i am doing something wrong.

foreach (var control in MainPanel.Controls
.Where(c => c is PictureBox) || c is TextBox)
{
MainPanel.Controls.Remove(control);
}
This will remove each item of types, both PictureBox and TextBox. The issue with this code of course is that you are modifying an collection whilst enumerating it.
One approach to resolving this issue could be to build a collection of controls to remove first
var controls = MainPanel.Controls.Where(c => c is PictureBox || c is TextBox).ToList();
And then to enumerate that collection removing each item from the Panel.
foreach (var toRemove in controls)
MainPanel.Controls.Remove(toRemove);
It would further benefit one to make sure that the item is removed from the UI on the correct thread
delegate void RemoveControlDelegate(Control controlToRemove);
private void RemoveControl(Control control)
{
if (InvokeRequired)
{
BeginInvoke(new RemoveControlDelegate(RemoveControl), control);
}
else
{
MainPanel.Controls.Remove(control);
}
}
foreach (var toRemove in controls)
RemoveControl(toRemove);

Look at MainPanel.Controls.OfType<PictureBox>() and MainPanel.Controls.OfType<TextBox>(). You can use this in conjunction with a .ToList() call to avoid modifying an interator while it's still active:
var PBs = MainPanel.Controls.OfType<PictureBox>().ToList();
var TBs = MainPanel.Controls.OfType<TextBox>().ToList();
foreach (var pb in PBs)
{
MainPanel.Controls.Remove(pb);
}
foreach (TextBox tb in TBs)
{
MainPanel.Controls.Remove(tb);
}

Turn textboxes and buttons visible when the number of tracks it's selected in a combobox

I'm trying to turn textboxes and buttons visible when the number of tracks it's selected in a combobox.
For example: when I select 3, just 3 textboxes and the 3 respective buttons to select the tracks are enabled. How can I change this code that I've made to a simple foreach or a for?
if (numero_faixas == 1) {
txtFaixa1.Visible = true;
btnFaixa1.Visible = true;
} else if (numero_faixas == 2) {
txtFaixa1.Visible = true;
btnFaixa1.Visible = true;
txtFaixa2.Visible = true;
btnFaixa2.Visible = true;
} else if (numero_faixas == 3) {
txtFaixa1.Visible = true;
btnFaixa1.Visible = true;
txtFaixa2.Visible = true;
btnFaixa2.Visible = true;
txtFaixa3.Visible = true;
btnFaixa3.Visible = true;
}

You can reduce the lines of code by changing your conditions, so you don't have to reference the same control so many times:
if (numero_faixas > 0)
{
txtFaixa1.Visible = true;
btnFaixa1.Visible = true;
}
if (numero_faixas > 1)
{
txtFaixa2.Visible = true;
btnFaixa2.Visible = true;
}
if (numero_faixas > 2)
{
txtFaixa3.Visible = true;
btnFaixa3.Visible = true;
}
To use a foreach loop, you could cast the Controls collection to an IEnumerable<Control> and then, using System.Linq;, you can filter on controls of type TextBox and Button, where the control name contains "Faxia". Then, in the loop body, we can use int.TryParse to try to convert the last character of the control name to an int, and if that succeeds, then set the control to Visible if the control number is less than numero_faixas + 1:
foreach (Control control in Controls.Cast<Control>()
.Where(c => (c is Button || c is TextBox) && c.Name.Contains("Faixa")))
{
// Get the number associated with this control and compare it to numero_faixas
int controlNumber;
if (int.TryParse(control.Name.Substring(control.Name.Length - 1), out controlNumber) &&
controlNumber < numero_faixas + 1)
{
control.Visible = true;
}
}

Here's a proof of concept that you could respin using your business rules.
using System;
using System.Drawing;
using System.Windows.Forms;
namespace ShowHideButtons_47439046
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
InitOurThings();
}
private void InitOurThings()
{
//lets create a combo box with options to select
ComboBox combo = new ComboBox();
combo.Location = new Point(5, 5);//place it somewhere
//add selectable items
for (int i = 0; i < 10; i++)
{
combo.Items.Add(i);
}
combo.SelectedValueChanged += Combo_SelectedValueChanged;//the event which will handle the showing/hidding
Controls.Add(combo);//add the combo box to the form
//lets create some buttons and textboxes
int btnx = 5;
int btny = combo.Height + combo.Location.Y + 5;
for (int i = 0; i < 10; i++)
{
Button btn = new Button();
btn.Location = new Point(btnx, btny);
btn.Name = i.ToString();
btn.Text = i.ToString();
Controls.Add(btn);
btny += btn.Height + 5;
TextBox txtbx = new TextBox();
txtbx.Location = new Point(btn.Location.X + btn.Width + 5, btn.Location.Y);
txtbx.Name = i.ToString();
txtbx.Text = i.ToString();
Controls.Add(txtbx);
}
}
private void Combo_SelectedValueChanged(object sender, EventArgs e)
{
int selectedValue = int.Parse(((ComboBox)sender).SelectedItem.ToString());
foreach (Control item in Controls)
{
//show/hide the controls based on their Name being Equal Or Smaller than the selectedItem
if (item is TextBox)
{
int itemNumber = int.Parse(item.Name);
item.Visible = itemNumber <= selectedValue ? true : false;
}
if (item is Button)
{
int itemNumber = int.Parse(item.Name);
item.Visible = itemNumber <= selectedValue ? true : false;
}
}
}
}
}

Remove a checkbox that is being created dynamically in a loop

I have a bunch of code that dynamicly creates some controls. It looks in a folder and lists the filenames in it. For each file in the folder it creates a checklistbox item, listbox item and two checkboxes. This is working great and as intended:
private void getAllFiles(string type)
{
try
{
string listPath = "not_defined";
if (type == "internal_mod")
{
int first_line = 76;
int next_line = 0;
int i = 0;
CheckBox[] chkMod = new CheckBox[100];
CheckBox[] chkTool = new CheckBox[100];
listPath = this.internalModsPath.Text;
string[] filesToList = System.IO.Directory.GetFiles(listPath);
foreach (string file in filesToList)
{
if (!internalModsChkList.Items.Contains(file))
{
internalModsChkList.Items.Add(file, false);
string fileName = Path.GetFileName(file);
internalModNameList.Items.Add(fileName);
//-----------------
// Draw Checkboxes
//-----------------
chkMod[i] = new CheckBox(); chkTool[i] = new CheckBox();
chkMod[i].Name = "modChk" + i.ToString(); chkTool[i].Name = "modChk" + i.ToString();
//chkMod[i].TabIndex = i; //chkTool[i].TabIndex = i;
chkMod[i].Anchor = (AnchorStyles.Left | AnchorStyles.Top); chkTool[i].Anchor = (AnchorStyles.Left | AnchorStyles.Top);
chkMod[i].Checked = true; chkTool[i].Checked = false;
chkMod[i].AutoCheck = true; chkTool[i].AutoCheck = true;
chkMod[i].Bounds = new Rectangle(549, first_line + next_line, 15, 15); chkTool[i].Bounds = new Rectangle(606, first_line + next_line, 15, 15);
groupBox7.Controls.Add(chkMod[i]); groupBox7.Controls.Add(chkTool[i]);
//-----------------
next_line += 15;
i++;
}
}
}
Now my problem is that I also want the user to be able to delete all these thing again based on the checklistbox' checked items.. I have no problems deleting the items in the checklistbox or the items in the listbox, but I want to remove the two checkboxes I create too ..
This is what I got to remove the items in the checklistbox, and the listbox
private void internalModListDel_btn_Click(object sender, EventArgs e)
{
int count = internalModsChkList.Items.Count;
for (int index = count; index > 0; index--)
{
if (internalModsChkList.CheckedItems.Contains(internalModsChkList.Items[index - 1]))
{
internalModsChkList.Items.RemoveAt(index - 1);
internalModNameList.Items.RemoveAt(index - 1);
groupBox7.Controls.Remove(modChk[index - 1]);
}
}
}
As you can see I have also tried to write something to remove the checkbox but it doesn't work and I have no idea how to make it work
Can you assist ?

Try using UserControls.
Use the ListBox controller to show those UserControls,
The user control can be built with those checkboxes, and the labels you want .
Another suggestion is to bind this list to an ObservableCollection which will contain the UserContorols you have created.
This way, it will be much more simlpe to add/remove/change the items inside.

Delete dynamically created controls

I keep getting stuck on this part of my program.
whenver i call an listbox.selectitemchange event, i want the proper amount of trackbar and labels to be displayed.
now, it does not work properly.
Some of them get removed when the event is called, some of them don't.
foreach (Label label in Controls.OfType<Label>())
{
if (label.Tag != null && label.Tag.ToString() == "dispose")
{
label.Dispose();
}
}
foreach (TrackBar trackBar in Controls.OfType<TrackBar>())
{
if (trackBar.Tag != null && trackBar.Tag.ToString() == "dispose")
{
trackBar.Dispose();
}
}
for (int i = 0; i < calc; i++)
{
//string[] LineWidthSplitted = lines[lineWidth].Split(' ');
//Int32.TryParse(LineWidthSplitted[2], out WidthValue);
Label Label = new Label();
Label.Name = "TrackbarWidth" + LabelName++;
Label.Tag = "dispose";
Label.Text = "Board -" + LabelName + "- Height:";
Label.Location = new Point(10, 450 + (50 * LabelName));
Label.Size = new System.Drawing.Size(100, 25);
this.Controls.Add(Label);
TrackBar trackBar = new TrackBar();
trackBar.Name = "TrackbarWidth" + trackbarName++;
trackBar.Tag = "dispose";
trackBar.Maximum = 85;
trackBar.Minimum = 65;
trackBar.SmallChange = 5;
trackBar.TickFrequency = 5;
trackBar.Value = 65;
trackBar.Location = new Point(150, 450 + (50 * trackbarName));
trackBar.Size = new System.Drawing.Size(100, 25);
this.Controls.Add(trackBar);
lineWidth += 4;
}
while, when i remove the foreach for the trackbar, all labels get properly displayed.
they all get deleted, en recreated for the pricese amount needed to be created, no exceptions.
Any reason why?
thank you.

Don't use "Dispose" on the labels right away. First remove them. Note that you can't modify the Controls collection inside the foreach so you have to do something like this:
List<Label> itemsToRemove = new List<Label>();
foreach (Label label in Controls.OfType<Label>())
{
if (label.Tag != null && label.Tag.ToString() == "dispose")
{
itemsToRemove.Add(label);
}
}
foreach (Label label in itemsToRemove)
{
Controls.Remove(label);
label.Dispose();
}
If you want to remove all different kinds of controls in one swoop:
List<Control> itemsToRemove = new List<Control>();
foreach (Control ctrl in Controls)
{
if (ctrl.Tag != null && ctrl.Tag.ToString() == "dispose")
{
itemsToRemove.Add(ctrl);
}
}
foreach (Control ctrl in itemsToRemove)
{
Controls.Remove(ctrl);
ctrl.Dispose();
}

I can't test this now, but I think you should also remove the controls from the Form Controls collection where you have added them. By the way, in your case I think you could avoid the OfType extension and use the old fashioned for..loop that will allow to execute just one loop....
for(int x = this.Controls.Count - 1; x >= 0; x--))
{
Control ctr = this.Controls[x];
if (ctr Is Label && ctr.Tag != null && ctr.Tag.ToString() == "dispose")
{
this.Controls.Remove(ctr);
ctr.Dispose();
}
if(ctr Is TrackBar && ctr.Tag != null && ctr.Tag.ToString() == "dispose")
{
this.Controls.Remove(ctr);
ctr.Dispose();
}
}
Notice how removing elements from a collection with a for..loop should be done in reverse order, from the end to start of the collection

Create control in runtime

I can't manage to get the values from textboxes that are created at run-time.
I want an user to choose something from a checkedlistbox, and to enter any values he wants in textboxes that are created at every button click.
How can I get the name of those texboxes? They really exist? I am a beginner and I really don't understand how they are created.
This is my code where I create textboxes.
private void checkedListBox1_SelectedIndexChanged(object sender, EventArgs e)
{
int x = 466;
int y = 84;
foreach (var itemChecked in checkedListBox1.CheckedItems)
{
int i = 0;
TextBox tb = new TextBox();
tb.Location = new Point(x, y);
tb.Name = "txtBox" + i++.ToString();
Controls.Add(tb);
y += 30;
}

just place the i outside the foreach and done.
int i = 0;
foreach (var itemChecked in checkedListBox1.CheckedItems)
{
i++;
string textBoxName = "textBox" + i.ToString();
TextBox tb = new TextBox();
tb.Location = new Point(x, y);
//tb.Name = "txtBox" + i++.ToString(); <--Your Version
tb.Name = textBoxName;
//...
//Other stuff or your codes
}

Rather than searching for exact name what you can do is have a string(fixed) which is searched for the control.
so if you find that string ( in your case which is 'textbox' ), what you can do is search for that fixed string in the name of control. if it exists then it's dynamically generated control.
foreach(Control c in parentControlIdOrName.Controls)
{
if(c.GetType()==typeof(TextBox))
{
if(((TextBox)c).Name.indexOf("textbox")!=-1)
{
// do your coding here...what ever you want....
}
}
}
Haven't tested but,Hope for the best. It might work.