Develop Reference

How to check if dynamic checkbox are checked

I've an application to import some pictures from a folder into another. I use picturebox to show my pictures and have a checkbox next to it. If it's unchecked i dont wanna import them.
So here is my code for creating a checkbox :
public void CreateCheckBox(Form formInstance,int yLocation, int xLocation, int iNumber)
{
CheckBox box = new CheckBox();
box.Name = "cbxName" + iNumber.ToString();
box.Location = new Point(xLocation+40,yLocation+90);
box.Visible = true;
box.Enabled = true;
box.Checked = true;
box.CheckedChanged += new EventHandler(cbx_CheckedChange);
formInstance.Controls.Add(box);
}
And my pictureBox :
public void CreatePictureBox(Form formInstance,int iNumber)
{
string[] tNomImage = RecupererNomImage();
PictureBox pbxImage = new PictureBox();
pbxImage.Name = "pbxName" + iNumber.ToString();
pbxImage.Image = Image.FromFile(tNomImage[iNumber]);
pbxImage.Width = 90;
pbxImage.Height = 90;
pbxImage.Location = new Point(iXLocation, iYLocation);
pbxImage.Visible = true;
pbxImage.BorderStyle = BorderStyle.FixedSingle;
pbxImage.SizeMode = PictureBoxSizeMode.Zoom;
formInstance.Controls.Add(pbxImage);
pbxImage.Enabled = false;
CreateCheckBox(this, iYLocation, iXLocation, iNumber);
if (iXLocation+iXSpacing*2 > this.Width)
{
iXLocation = XLOCATION;
iYLocation += iXSpacing;
}
else
{
iXLocation += iXSpacing;
}
And I wanna know which checkbox is checked so I can export the picture next to it.

I presume a picturebox will have a name like:
pbxName141
And its matching checkbox will have a name like:
cbxName141
You can ask the form for all the checked boxes:
var cbs = formInstance.Controls.OfType<CheckBox>().Where(cb => cb.Checked);
You can convert the checkbox name into the related picturebox name and look up the picturebox by name:
foreach(var cb in cbs){
var pbName = "p" + cb.Name.Substring(1);
var pb = formInstance.Controls[pbName];
}
So many ways to skin this cat..

Change your methods so that they RETURN the control that was created:
public CheckBox CreateCheckBox(Form formInstance,int yLocation, int xLocation, int iNumber)
{
// ... existing code ...
return box;
}
Now you can store a reference to that CheckBox in the Tag() property of the PictureBox:
public PictureBox CreatePictureBox(Form formInstance,int iNumber)
{
// ... existing code ...
CheckBox cb = CreateCheckBox(this, iYLocation, iXLocation, iNumber);
pbxImage.Tag = cb;
// ... existing code ...
return pbxImage;
}
Finally, add all of those returned PictureBoxes to a List<PictureBox> so you can easily reference and iterate over them. Simply cast the control stored in the Tag() property back to a CheckBox and you can determine if each PictureBox should be imported or not.

List<CheckBox> c = Controls.OfType<CheckBox>().Cast<CheckBox>().ToList();
forech(CheckBox item in c){
if(c.checked){
}
}

Create dynamic buttons in a grid layout - Create a magic square UI

I'm supposed to create a magic square in 2D using Windows Forms Application. It should look like this:
However, the user should be able to decide the size of the square (3x3, 5x5, 7x7, etc). I already wrote the code in a Console Application, but I don't know how to add the 2D graphics.
Somebody already asked this question (How do I put my result into a GUI?), and one of the answers was to use DataGridView, but I'm not sure if that's what I'm looking for, since I can't make it look like the picture.
Any ideas or advice?

You can use a TableLayoutPanel and add buttons to panel dynamically.
If you don't need interaction with buttons, you can add Label instead.
Create square dynamically:
public void CreateSquare(int size)
{
//Remove previously created controls and free resources
foreach (Control item in this.Controls)
{
this.Controls.Remove(item);
item.Dispose();
}
//Create TableLayoutPanel
var panel = new TableLayoutPanel();
panel.RowCount = size;
panel.ColumnCount = size;
panel.BackColor = Color.Black;
//Set the equal size for columns and rows
for (int i = 0; i < size; i++)
{
var percent = 100f / (float)size;
panel.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, percent));
panel.RowStyles.Add(new RowStyle(SizeType.Percent, percent));
}
//Add buttons, if you have your desired output in an array
//you can set the text of buttons from your array
for (var i = 0; i < size; i++)
{
for (var j = 0; j < size; j++)
{
var button = new Button();
button.BackColor = Color.Lime;
button.Font = new Font(button.Font.FontFamily, 20, FontStyle.Bold);
button.FlatStyle = FlatStyle.Flat;
//you can set the text of buttons from your array
//For example button.Text = array[i,j].ToString();
button.Text = string.Format("{0}", (i) * size + j + 1);
button.Name = string.Format("Button{0}", button.Text);
button.Dock = DockStyle.Fill;
//If you need interaction with buttons
button.Click += b_Click;
panel.Controls.Add(button, j, i);
}
}
panel.Dock = DockStyle.Fill;
this.Controls.Add(panel);
}
If you need interaction with buttons
void button_Click(object sender, EventArgs e)
{
var button = (Button)sender;
//Instead put your logic here
MessageBox.Show(string.Format("You clicked {0}", button.Text));
}
As an example, you can call
CreateSquare(3);
Screenshot:

You can create a Form and add a TableLayoutPanel with this property
tableLayoutPanel1.Dock = DockStyle.Fill;
tableLayoutPanel1.BackColor = Color.Gold;
and this is the result
When you create Row and Column, to fit correctly set the percentage in this way:
After this you can add a Button or Label in each square.

dynamically creating window form according to data returned from dataset (C#)

I have a dataset that returns questions and answers from the database, each answer in answer table is linked via a forgein key to the question table.
What I would like to achive is the following:
That a a single dynamic form is created on the first question with all the questions listed under it, meaning the FK_table_Answers = PK_table_Questions on the table_Answers:
(eg) This is Form for Question One:
Question One: How old are you?
Answer One (this is a radio button)
Answer Two (this is a radio button)
Answer Three (this is a radio button)
I have managed to get the above kind of working but the problem is my code keeps generating the forms (eg) 3 times becuase there are three answers, so can anyone point me in right direction how to generate the form dynamically but only ONCE - meaning each successive form is created only once as per the question and that particular questions answers under it.
Kind regards
UPDATED code:
private void LoadDataSets()
{
if (_dataSetQuestionnaire.tbl_QuestionnaireQuestion.Rows.Count == 0)
{
try
{
//Questionnaire:
DataSet1TableAdapters.tbl_QuestionnaireTableAdapter questionnaireAdapter =
new DataSet1TableAdapters.tbl_QuestionnaireTableAdapter();
questionnaireAdapter.Fill(_dataSetQuestionnaire.tbl_Questionnaire);
//Category:
DataSet1TableAdapters.tbl_QuestionnaireCategoryTableAdapter categoryAdapter =
new DataSet1TableAdapters.tbl_QuestionnaireCategoryTableAdapter();
categoryAdapter.Fill(_dataSetQuestionnaire.tbl_QuestionnaireCategory);
//QuestionnaireQuestion:
DataSet1TableAdapters.tbl_QuestionnaireQuestionTableAdapter questionnaireQuestionAdapter =
new DataSet1TableAdapters.tbl_QuestionnaireQuestionTableAdapter();
questionnaireQuestionAdapter.Fill(_dataSetQuestionnaire.tbl_QuestionnaireQuestion);
//QuestionnaieAnswer:
DataSet1TableAdapters.tbl_QuestionnaireAnswerTableAdapter questionnaireAnswerAdapter =
new DataSet1TableAdapters.tbl_QuestionnaireAnswerTableAdapter();
questionnaireAnswerAdapter.Fill(_dataSetQuestionnaire.tbl_QuestionnaireAnswer);
using (DataSet1 dSet = new DataSet1())
{
//Questionnaire:
dSet.Merge(_dataSetQuestionnaire.tbl_Questionnaire);
//Category:
dSet.Merge(_dataSetQuestionnaire.tbl_QuestionnaireCategory);
//QuestionnaireQuestion:
dSet.Merge(_dataSetQuestionnaire.tbl_QuestionnaireQuestion);
//QuestionnaieAnswer:
dSet.Merge(_dataSetQuestionnaire.tbl_QuestionnaireAnswer);
int primaryKeyQuestionnaire = Convert.ToInt32(_dataSetQuestionnaire.tbl_Questionnaire.Rows[0][0]);
foreach (DataSet1.tbl_QuestionnaireRow questionnaire
in _dataSetQuestionnaire.Tables["tbl_Questionnaire"].Select(String.Format("pk_tbl_Questionnaire = {0}", primaryKeyQuestionnaire)))
{
foreach (DataSet1.tbl_QuestionnaireCategoryRow category
in _dataSetQuestionnaire.Tables["tbl_QuestionnaireCategory"].Select(String.Format("fk_tbl_Questionnaire = {0}", questionnaire.pk_tbl_Questionnaire)))
{
foreach (DataSet1.tbl_QuestionnaireQuestionRow question
in _dataSetQuestionnaire.Tables["tbl_QuestionnaireQuestion"].Select(String.Format("fk_tbl_QuestionnaireCategory = {0}", category.pk_tbl_QuestionnaireCategory)))
{
int radiobuttonPosition = 0;
foreach (DataSet1.tbl_QuestionnaireAnswerRow answer
in _dataSetQuestionnaire.Tables["tbl_QuestionnaireAnswer"].Select(String.Format("fk_tbl_QuestionnaireQuestion = {0}", question.pk_tbl_QuestionnaireQuestion)))
{
//Gets the questins via the FK_questionnaireQuestion and fill the _dataSetRadioButtons to generate on dynamic form.
DataSet1TableAdapters.tbl_QuestionnaireAnswerTableAdapter a =
new DataSet1TableAdapters.tbl_QuestionnaireAnswerTableAdapter();
DataSet dSetRadioButtons = new DataSet();
dSetRadioButtons.Merge(a.GetDataByQuestionnaireQuestion(answer.fk_tbl_QuestionnaireQuestion));
_dataSetRadioButtons = dSetRadioButtons;
string theQuestion = question.tbl_QuestionnaireQuestion_Description.ToString();
Form form = new Form();
_form = form;
if(_form == null)
{
_form = new Form();
}
else
{
form.Height = 400;
form.Width = 550;
form.StartPosition = FormStartPosition.CenterScreen;
Label label = new Label();
label.Location = new System.Drawing.Point(5, 10);
label.Size = new System.Drawing.Size(450, 25);
label.Text = theQuestion;
Panel panel = new Panel();
panel.Size = new System.Drawing.Size(300, 200);
panel.Location = new System.Drawing.Point(15, 50);
panel.BackColor = Color.Yellow;
System.Windows.Forms.RadioButton[] radioButtons = new System.Windows.Forms.RadioButton[_dataSetRadioButtons.Tables["tbl_QuestionnaireAnswer"].Rows.Count];
for (int i = 0; i < _dataSetRadioButtons.Tables["tbl_QuestionnaireAnswer"].Rows.Count; i++)
{
radioButtons[i] = new RadioButton();
radioButtons[i].Text = _dataSetRadioButtons.Tables["tbl_QuestionnaireAnswer"].Rows[i]["tbl_QuestionnaireAnswer_Description"].ToString();
radioButtons[i].Location = new System.Drawing.Point(60, 20 + i * 20);
//panel.Controls.Add(radioButtons[i]);
radioButtons[i].Click += new EventHandler(Form1_Click);
Int64 item = Convert.ToInt64(_dataSetRadioButtons.Tables["tbl_QuestionnaireAnswer"].Rows[0].ItemArray[3].ToString());
panel.Controls.Add(radioButtons[i]);
}
Button nextButton = new Button();
nextButton.Text = "Next";
nextButton.Name = "button";
nextButton.Location = new System.Drawing.Point(200, 300);
nextButton.Size = new System.Drawing.Size(150, 25);
nextButton.Click += new EventHandler(nextButton_Click);
form.Controls.AddRange(new Control[] { panel, label, nextButton });
form.ShowDialog();
CreateBoxAndQuestion(form, panel, label);
//form.Dispose();
}
}
}
}
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
else
{
MessageBox.Show("Error");
}
}
private void CreateBoxAndQuestion(Form f, Panel p, Label l)
{
for (int i = p.Controls.Count - 1; i >= 0; i--)
{
p.Controls.RemoveAt(i);
}
}

If I understand correctly, you call CreateBoxAndQuestion every time a new question is selected.
But you create (and destroy) the form each time your code enters in this method.
A first approach would be to keep the form, label, button and panel creation outside the method (perhaps in design mode) then passing these controls to the method as
EDIT: Somewhere in your code before entering the load of your next question:
frmQuestion _form = null; // Global
// Create a global instance and keep it without displaying
if(_form == null) _form = new frmQuestion(); // frmQuestion created with panel, label e button via FormDesigner
then when you need to populate _form call
CreateBoxAndQuestion(_form, _form.Panel, _form.Label, questionText);
In this example I pass the _form to CreateBoxAndQuestion, but this is not necessary because is a global. You could change CreateBoxAndQuestion to use directly the global instance.
private void CreateBoxAndQuestion(frmQuestion f, Panel p, Label l, string _label)
{
// Do not display your form here....
}
Now when entering the method clear every RadioButton controls in the panel.Controls collection
for (int i = p.Controls.Count - 1; i >= 0; i--)
{
p.Controls.RemoveAt(i);
}
the rest of the code should change only to reflect the new text assigned to the label and controls and the re-adding of the RadioButtons to the panel. No more creation and reinitialization for Form Label, Button.
label.Text = _label;
Don't forget to destroy _form at the end of your program with _form.Dispose();

Dynamically created trackbars and Labels and linking them together in C#

I am trying to create trackbars and labels dynamically. In which if a user inputs a number like 4, it creates 4 trackbars and 4 labels. Then if the user moves any of the dynamically created trackbar moves it and updates its associated label. Then adds the numbers in all the labels and stores it in another label call total label.
Here is another way of explaining it. The user enters the number 3. The system creates 3 trackbars and 3 labels (next to the trackbars). The user moves first track bar to 5, the first label is automatically updated with 5. The user moves the second track bar to 3, the second label is automatically updated with 3. finally the user moves the third track bar to position 9 and the label is automatically updated with 9.
On the right side there is another label that shows 17 = (5+3+9).
I found a few websites ons creating dynamically controls but I don't know how to link a dynamically created trackbar to the dynamically created label. Then adding those dynamically added labels.
ALL this in C# on a windows form.
I did something very simliar to the below when creating my labels and trackbars.
for (int i = 0; i < 10; i++)
{
Label label = new Label();
label.Text = i.ToString();
PlaceHolder1.Controls.Add(label);
}
Thanks in advances
------------------------Update-----------------
void CreateLabeledTrackBars(Control host, int n)
how do I use this, I was hoping that when I start a new form
that all I would have to is this..that way the form already has the in n, but it seems not to work..i am confused on how the control works. can you please explain
namespace WindowsFormsApplication1
{
public partial class Form3 : Form
{
public static Form2 myNewForm = new Form2();
private TrackBar[] _trackBars;
private Label[] _labels;
public Form3(int n)
{
CreateLabeledTrackBars(new Label (), n);
}
//Then the rest of the code

You need to handle ValueChanged event of each TrackBar you create. To calculate sum of all values, store created controls in arrays.
private TrackBar[] _trackBars;
private Label[] _labels;
void CreateLabeledTrackBars(Control host, int n)
{
const int trackBarWidth = 150;
const int minValue = 0;
const int maxValue = 10;
const int defaultValue = 0;
_trackBars = new TrackBar[n];
_labels = new Label[n];
int y = 0;
for(int i = 0; i < n; ++i)
{
var label = new Label()
{
Top = y,
Left = trackBarWidth,
Text = defaultValue.ToString(),
Parent = host,
};
var trackBar = new TrackBar()
{
Top = y,
Width = trackBarWidth,
// save associated label
Tag = label,
Minimum = minValue,
Maximum = maxValue,
Value = defaultValue,
Parent = host,
};
// handle ValueChangedEvent
trackBar.ValueChanged += OnTrackBarValueChanged;
// apply vertical offset for next trackbar
y += trackBar.Height;
_trackBars[i] = trackBar;
_labels[i] = label;
}
}
void OnTrackBarValueChanged(object sender, EventArgs e)
{
// get trackbar, which generated event
var trackBar = (TrackBar)sender;
// get associated label
var associatedLabel = (Label)trackBar.Tag;
associatedLabel.Text = trackBar.Value.ToString();
// recalculate sum of all values and update other label here
}
Now, when you have an array of trackbars, getting sum of all values should be trivial.

Is there anyway to set a value of a hidden control?

I have a hidden control which contains a textbox control and I want to set the text property of the textbox but i get an NullReferenceException. However if I show the control, set the value and then hide it then i get no exception.
miStatus1.Show();
miStatus1.ioItem1.popIoItem(caseState);
miStatus1.Hide();
However this feels like a really unclean and not very elegant way to do it. And i'm seeing some flickering because i have to do this to 4 controls with up to 8 textboxes on each.
Is there any way to set the text propery of the textboxes while the control is hidden? Or is it perhaps a better idea to populate my textboxes when showing the control? And will this slow down my application as it needs to populate everytime the control is shown?
popIoItem - code
public void popIoItem(object obj){
if (ioType == 1)
{
tb.Text = (string)obj;
}
}
My interface
I'm trying to create the menu to the right and on each pressing of the categories the menus slide up/down and i hide/show the proper user control with the textboxes and other io-elements.
More code
When one of the boxes to the left is click'ed the following method is run:
public void openMenu(int caseNum)
{
caseDB.casesDataTable chosenCase;
chosenCase = _casesAdapter.GetDataByID(caseNum);
string caseName = "";
int caseOwner = -1;
DateTime caseDate = DateTime.Today;
string caseDesc = "";
int caseState = -1;
foreach (caseDB.casesRow casesRow in chosenCase)
{
if (!casesRow.IscaseNameNull())
caseName = casesRow.caseName;
if (!casesRow.IscaseCreatedByNull())
caseOwner = casesRow.caseCreatedBy;
if (!casesRow.IscaseCreatedNull())
caseDate = casesRow.caseCreated;
if (!casesRow.IscaseDescNull())
caseDesc = casesRow.caseDesc;
if (!casesRow.IscaseStateNull())
caseState = casesRow.caseState;
}
int caseJobs = (int)_jobsAdapter.JobCount(caseNum);
string caseStateStr = Enum.GetName(typeof(caseState), caseState);
caseInfoMenu1.popMenu(caseName, caseOwner, caseDate, caseDesc,caseJobs,caseStateStr);
}
The caseInfoMenu is the right menu. It consists of some drawing and mouse logic that draws the menu and handles hit-detection. Besides this it contains 4 user controls, one for each of the vertical tabs.
public void popMenu(string caseName, int caseOwner ,DateTime caseDate, string caseDesc, int caseJobs, string caseState)
{
marked = 0;
miGeneral1.Show();
miEconomy1.Hide();
miStatus1.Hide();
miHistory1.Hide();
miGeneral1.ioItem1.popIoItem(caseName);
miGeneral1.ioItem2.popIoItem(caseOwner.ToString());
miGeneral1.ioItem3.popIoItem(caseDate.ToShortDateString());
miGeneral1.ioItem4.popIoItem(caseJobs.ToString());
miGeneral1.ioItem5.popIoItem(caseDesc.ToString());
//miStatus1.ioItem1.popIoItem(caseState);
//This is commented out because it makes the application crash. However if I show miStatus1, set the value and hide it, it does not crash.
this.Invalidate();
}
Inside each of these user controls I have io-items user controls which essentially draws a blue box and puts a control in front of if ie. the textbox.
public partial class ioItem : UserControl
{
public int ioType { get; set; }
public int ioPadding { get; set; }
RichTextBox tb;
public ioItem()
{
InitializeComponent();
}
public void popIoItem(object obj){
if (ioType == 1)
{
tb.Text = (string)obj;
}
}
private void ioItem_Load(object sender, EventArgs e)
{
switch (ioType)
{
case 1:
tb = new RichTextBox();
tb.Location = new System.Drawing.Point(ioPadding, ioPadding);
tb.Name = "textbox";
tb.Size = new Size(this.Size.Width - (ioPadding * 2), this.Size.Height - (ioPadding * 2));
tb.BorderStyle = BorderStyle.None;
tb.Visible = true;
tb.BackColor = Color.FromArgb(255, 184, 198, 208);
tb.Font = new Font("Microsoft Sans Serif", 7);
this.Controls.Add(tb);
break;
case 2:
historyCtrl hiCtrl = new historyCtrl();
hiCtrl.Location = new Point(0,0);
hiCtrl.Size = new Size(this.Width, this.Height);
hiCtrl.Name = "history";
hiCtrl.Visible = true;
hiCtrl.BackColor = Color.FromArgb(255, 184, 198, 208);
this.Controls.Add(hiCtrl);
break;
default:
goto case 1;
}
}
}

Try checking the code with debugger..May be there is something other going on there? NullReference means that you try to do something with object that doesn't exist. Show/Hide just set Visible property of the control to true/false in normal situation(without custom overload/changes of Control class).

So i figured out what was wrong. The problem was something else than what I initially expected. The reason why it didn't work was because I created my textbox controls in the Load_event. When I tried to set the value of the text property of the textbox controls they hadn't been created yet. The reason why I had created the user controls containing the textboxes this way was in order to make it easy to drag them into the screen in the Designer. I found this discussion 'UserControl' constructor with parameters in C#, which showed me another way of doing it and now it works.