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Is there a way to dynamically generate code to interact with buttons in C#?

I'm trying to find a a way to be able to essentially dynamically generate code based on an input.
For example I could type something like:
int Number = 22;
Button<Number>.Text = "X";
So in this case it would set button22 to have its text be an "X".
And I could change it so that I could input, for example 24 into the program and it would then set button24 to be an "X", instead of setting up a bunch of if statements to cover every potential button press.
For further context I have a Grid of 64 buttons and I need to be able to edit them individually to show to the user which buttons have been pressed, it is possible to do it with a lot of if statements but I thought it might be worth trying to find a more elegant solution.

You could have a list of buttons:
private List<Button> _buttons = new List<Button>();
Populate it like this:
for (int i = 0; i < 10; i++)
{
var b = new Button();
b.Text = $"Button #{i}";
b.Click += HandleButtonClick;
}
And you could even set an event handler on one of its events which doesn't even need to use the list (the sender is the source of the event):
private void HandleButtonClick(object sender, EventArgs e)
{
(sender as Button).Text = "X";
}

Buttons have a Tag property that can be used to hold arbitrary data about a button, this is described for WinForms, WPF and UWP.
Simple usage that is similar to OP's requirement is demonstrated in this SO post
This situation is in a practical sense the very reason that .Tag exists at all in user interface controls pretty much from the birth of c#.
So you do not need to use a custom class for a button, just simply assign your value to the .Tag property on the Button class that you are creating programmatically:
in this example a list is used to create the buttons and separate the creation from the layout, it is not necessary to do this, but may be useful. Instead, you could assign this button to it's parent container and/or set the layout margins or coordinates without keeping a reference to the Button object at all.
If OP updates the post to include implementation examples, we can update this response with more specific and complete code.
private List<Button> _buttons = new List<Button>();
// ... iteration or switching logic
var nextButton = new Button
{
Text = "x",
Tag = 22
};
nextButton.Click += DynamicButton_Click;
_buttons.Add(nextButton);
// ... later push the buttons into the parent container or bind to the UI
Then the button click handler you can access this Tag property:
this is presented from WinForms, the only difference in UWP or WPF is the method signature, change EventArgs to RoutedEventArgs
private void DynamicButton_Click(object sender, EventArgs e)
{
if(int.TryParse((sender as Button).Tag?.ToString(), out int buttonValue))
{
// use buttonValue
Console.Out.WriteLine(buttonValue);
}
else
{
// Otherwise, sender was not a button, or the button did not have an integer tag value
// either way, handle that error state here...
}
}
Using these concepts, once the buttons are created, let's say in some simple grid alignment, you could allow the user to set this Tag value at runtime if you have a TextBox (or other) input field that can be accessed from the code.
I recommend that you use MVVM style bindings for this rather than directly referencing a TextBox control, but this is simply to demonstrate the point.
private void DynamicButton_Click(object sender, EventArgs e)
{
// assign the string value from the ButtonValueTextbox control to this button
string value = this.ButtonValueTextBox.Text;
if(sender is Button button)
{
button.Tag = value;
}
else
{
// Otherwise, sender was not a button
// handle the error state here if you need to...
}
}
Now that each button has a tag, you could easily add logic to maintain unique tag values by iterating through the other buttons and clearing the tag if it was previously assigned to a different button.

Maybe you could keep a List of Button References:
var myButtons = new List<Button>();
myButtons.Add(firstButton);
myButtons.Add(secondButton);
// ... etc
// ... then somewhere else
int number = 3;
myButtons[number].Text = "xxx";

Convert a string value into PlaceHolder id

As a newbie I have tried several Google searches and have found a few confusing answers. What I am trying to achieve is:
click on a button (one of many),
extract that button's text value, then
use that value to make the relevant placeholder visible.
So far I have done the first 2 steps but how do I accomplish step 3? My code so far, which works if I click on the Asia button, is:
protected void btnArea_Click(object sender, EventArgs e)
{
string ar = (sender as Button).Text;
//ar = "Asia";
phdasia.Visible = true;
}
In simple, newbie friendly terms, what do I have to insert in place of phdasia?

If your placeholder controls share the same name format you may be able to reach them by name:
protected void btnArea_Click(object sender, EventArgs e)
{
string ar = (sender as Button).Text;
//ar = "Asia";
string name = "phd" + ar.ToLower(); // The naming format comes here
Control[] controls = this.Controls.Find(name, true); //find the control(s) by name
foreach(Control control in controls) // mow loop and make them visible
control.Visible = true;
//phdasia.Visible = true;
}
Edit: alternatively you can use FindControl method to locate a control with an ID property of "phdasia" on the containing page:
Control control = FindControl(name);
if(control!=null)
control.Visible = true;

How to access dynamically created controls in C#?

I have dynamically created checkbox's. I have an option "Select All". How do I select all the dynamically created checkboxes in C#?
How to select all the dynamic checkboxes which have been created?
protected void chkbox_CheckedChanged(object sender, EventArgs e)
{
CheckBox chkBtn = new CheckBox();
chkBtn = sender as CheckBox;
selectedTypeId.Add(Convert.ToInt16(chkBtn.Name));
foreach(int id in selectedTypeId)
{
Console.WriteLine(id);
}
}

Declare a global List of CheckBoxes:
List<CheckBox> boxes;
And on your program start instantiate it.
boxes = new List<CheckBox>();
Each time you dynamically add a CheckBox, also add it to your List.
CheckBox chkBtn = new CheckBox();
boxes.Add(chkBtn);
When you want to check them all at once, use a loop to go through the list.
foreach(CheckBox box in boxes)
box.Checked = true;

You can get all of the CheckBoxes of the control like so:
var checkBoxes = this.Controls.OfType<CheckBox>();
checkBoxes.ToList()?.ForEach(x=>x.Checked = true);
But typically you would put all of the checkboxes in groupbox (from ux perspective)
groupBox.Controls.Add(checkBox);
and then get them from the groupbox:
var checkBoxes = groupBox.Controls.OfType<CheckBox>();

Checking if the Checkbox is checked or not dynamically in c#

I have created a Checkbox dynamically by this button code
private void btn_add_record_Click(object sender, EventArgs e)q2
{
CheckBox DeleteCheckBox = new CheckBox();
Point P_request = new Point(nXCheckBox, nYCheckBox);
DeleteCheckBox.Location = P_request;
DeleteCheckBox.Name = "CH"+Record_ID+"";
}
Then i Checked it manually
Then i need to check a specific checkbox its name is "CH"+Record_ID+" to be checked or not dynamically using this code
string ChechBoxName = "CH1";
CheckBox DeleteChechBox = new CheckBox();
DeleteChechBox.Name = ChechBoxName;
if (DeleteChechBox.Checked)
{
// To Do Code
}
When i debug this code, it doesn't enter the if statement .. WHY ?

You're checking if the box is checked before it gets checked. Add
DeleteChechBox.CheckedChanged += DeleteChechBoxCheckedChanged;
and add the method DeleteChechBoxCheckedChanged where you can test whether or not it's been checked. You can also use
DeleteChechBox.Checked = true;
to check the box through code.
Edit:
To get a certain checkbox by it's name you have to either store it as a global variable or look through the controls array in the form.
foreach (Control control in this.Controls)
{
if (control.Name == "CH1")
{
CheckBox DeleteChechBox = (CheckBox)control;
if (DeleteChechBox.Check)
{
//To Do Code
}
}
}

When you create a new CheckBox, the default Checked value is false. Therefore if (DeleteChechBox.Checked)
returns false which is why you don't enter the block. You're not checking any existing Checkboxes, you're checking the new one you created.

In WPF you can accomplish it like shown in the following code snippet (pertinent to your example):
string _strCheckBoxName = "CH1";
CheckBox DeleteCheckBox= new CheckBox();
DeleteCheckBox.Name = _strCheckBoxName ;
DeleteCheckBox.Checked+=(s,e)=>CheckBox_Change(s,e);
DeleteCheckBox.Unchecked+=(s,e)=>CheckBox_Change(s,e);
DeleteCheckBox.IsChecked = true;
private void CheckBox_Change(object sender, RoutedEventArgs e)
{
if ((sender as CheckBox).Name=_strCheckBoxName && (bool)(sender as CheckBox).IsChecked)
{
// To Do Code
}
}
In suggested solution, you essentially subscribe the newly created CheckBox control to a single event handler proc, which looks at the control name and if checked runs some code. If more CheckBox added, then use the same event-subscription technique pointed to the same handler, and extend it with another if statement (or if-else if, or switch statement).
Hope this will help. Rgds,

Your problem is that you are creating one CheckBox in your btn_add_record_Click handler and then creating a new one in your second code fragment, which just happens to have the same Name as the first. That notwithstanding, it is not the same check box, so will not have the same value for its Checked property.
The way to fix that is to create the checkbox in the form's constructor as a class member, and then discover it when you need it by searching the components, using the code which Xylorast showed:
foreach (Control control in this.Controls)
{
if (control.Name == "CH1")
{
CheckBox DeleteChechBox = (CheckBox)control;
if (DeleteChechBox.Check)
{
//To Do Code
}
}
}

This is what I meant. Maybe you already checked it..?
string ChechBoxName = "CH1";
CheckBox DeleteChechBox = new CheckBox();
DeleteChechBox.Name = ChechBoxName;
DeleteChechBox.Checked = true;
if (DeleteChechBox.Checked)
{
// To Do Code
}
Edit:
Here is another way of accessing the control instead of enumerating over all the controls on the form for each control you would like to access:
Dictionary<string, CheckBox> checkBoxCollection = new Dictionary<string, CheckBox>();
And in your method where you create the checkbox add it to the dictionary:
checkBoxCollection.Add("CH1",DeleteCheckBox);
Access the checkbox from wherever you want like this:
CheckBox checkBox;
bool success = controls.TryGetValue("CH1"), out checkBox);
if (success)
{
// To Do Code
}
Or in your CheckedEvent you can get the CheckBox being checked like this:
CheckBox checkBox = sender as CheckBox;

Iterating through textboxes using asp.net

I am building a page with asp.net. I have a form with a table that contains TextBoxes and a submit button. When the form is submitted, I want to grab all the text that was entered into the TextBoxes and operate on them. To do this, I have the following method:
protected void Button1_Click(object sender, EventArgs e)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder();
foreach (Control c in this.Controls)
{
if (c.GetType().Name == "TextBox")
{
TextBox tb = (TextBox)c;
sb.AppendLine(tb.Text);
}
}
Label1.Text = sb.ToString();
}
The problem with this is that the controls apparently doesn't include any of my textboxes. When I iterate through the controls and print out their names, the only one I get is "site_master." (I also tried Controls and Page.Controls instead of this.Controls).
Is there something wrong with my iterator? Is there another way in which I could iterate through all of the textboxes in the table or page? What is the best way to accomplish this?

Would it be too much to build a List<Textbox>, given you know all your textbox controls?
List<Textbox> txtBoxes = new List<Textbox>();
txtBoxes.Add(tb1);
txtBoxes.Add(tb2);
//etc..
Then you have a nice list to work with

If I knew the controls were all in a given containing control, I would simply poll the controls of that control. For example, this.Form.Controls. However, if they could be nested within other child controls, then you could recursively explore the depths from a common outer container.
private IEnumerable<T> FindControls<T>(Control parent) where T : Control
{
foreach (Control control in parent.Controls)
{
if (control is T)
yield return (T)control;
foreach (T item in FindControls<T>(control))
yield return item;
}
}
So this would allow you to retrieve all TextBox children.
List<TextBox> textBoxes = this.FindControls<TextBox>(this).ToList();
string output = string.Join(",", textBoxes.Select(tb => tb.Text));

I'm going to assume that you are using web forms ASP.NET. Typically you declare your controls on the aspx page using something similar to
<asp:TextBox ID="someId" runat="server/>
If you have done this then in your code behind your should just be able to reference the variable someId and the property Text to get/set the text in the control.
If you are building the controls dynamically on the server you should be able to stick them in a list and iterate through it. Make sure you are creating the controls and adding them to the table during the correct part of the page lifecycle. When you add them to a cell in the table you could also keep a reference to the control in a list and just enumerate through that list in your event handler.
Maybe something along the lines of (I didn't compile this so there are probably issues):
public class MyPage: Page
{
private List<TextBox> TxtBoxes = new List<TextBox>();
//registered for the preinit on the page....
public void PreInitHandler(object sender, EventArgs e)
{
for(var i = 0; i < 2; i++)
{
var txtBox = new TextBox{Id = textBox+i};
//...add cell to table and add txtBox Control
TxtBoxes.Add(txtBox);
}
}
}