Develop Reference

Change text of a TextBox clicking a Button with Controls created at run-time

I'm trying to change the text of a TextBox when I click a Button: both Controls are dynamically created as run-time.
The Buttons and the TextBoxes are created every time I click on another Button.
The Name Property for each control is specified by the User, using a TextBox.
For example, the user inputs "Test1", then the Button is named btn_Test1, and the TextBox is named txt_Test1.
The Button should open a FolderBrowserDialog and after a selection has been made, the TextBox shows the path selected.
I'm using the following code:
protected void button_Click(object sender, EventArgs e)
{
Button button = sender as Button;
folderBrowserDialog.ShowDialog();
string TextName = button.Name.Replace("btn_", "txt_");
TextBox selectText = new TextBox();
selectText = this.Controls[TextName] as TextBox;
selectText.Text = folderBrowserDialog.SelectedPath;
}
however this part gives me null:
selectText = this.Controls[TextName] as TextBox;
I did check with the debugger when I create the controls, so TextName is setting the correct Name.
The Buttons and TextBoxes are inserted in a TabControls, the Tab Name is set to the value the user inputs, so the main TabControl gets 2 controls.
I'm using a hidden TabControl named "TabFolders" that will be the main reference for creating tab clones
I'm using this code:
private void CreateDynamicPathButtons(string TabName)
{
TabPage MyNewTab = new TabPage(TabName);
TabPage TabCopy1;
tabControlEmpresas.TabPages.Add(MyNewTab);
TabControl tc = new TabControl();
tc.Location = new System.Drawing.Point(6, 6);
tc.Size = TabFolders.Size;
for (int i = 0; i < TabFolders.TabCount; i++) {
TabFolders.SelectTab(i);
TabCopy1 = new TabPage(TabFolders.SelectedTab.Text);
foreach (Control c in TabFolders.SelectedTab.Controls) {
Control cNew = (Control)Activator.CreateInstance(c.GetType());
cNew.Text = c.Text;
cNew.Size = c.Size;
cNew.Location = new System.Drawing.Point(c.Location.X, c.Location.Y);
cNew.Visible = true;
if (cNew is TextBox) {
cNew.Name = "txt_" + MyNewTab.Text + "_" + TabFolders.SelectedTab.Text;
}
if (cNew is Button) {
cNew.Name = "btn_" + MyNewTab.Text + "_" + TabFolders.SelectedTab.Text;
cNew.Click += new EventHandler(button_Click);
}
TabCopy1.Controls.Add(cNew);
}
tc.TabPages.Add(TabCopy1);
}
MyNewTab.Controls.Add(tc);
}

After many attempts I did find a very simple solution.
TextBox selectText = new TextBox();
selectText = button.Parent.Controls[TextName] as TextBox;
The button parent hast all the controls.

Assuming that button is the Button control you're creating at run-time you mentioned, you're creating a TextBox control but you're not adding it to the Form.Controls collection (this.Controls.Add([Control])).
Also, you should assign a Location, using a logic that fits your current Layout, to position the newly created Controls. Otherwise, all new controls will be positioned one on top of the other. In the example, the new Control position is determined using a field (int ControlsAdded) that keeps track of the number of Controls created at run-time and add some basic layout logic.
But, if you want to keep a reference of these new Controls, you should add them to a List<Control> or some other collection that allows to select them if/when required.
int ControlsAdded = 0;
protected void button_Click(object sender, EventArgs e)
{
TextBox selectedText = new TextBox();
selectedText.Size = new Size(300, this.Font.Height);
selectedText.Location = new Point(100, ControlsAdded * selectedText.Height + 30);
ControlsAdded += 1;
this.Controls.Add(selectedText);
selectedText.BringToFront();
using (var fBD = new FolderBrowserDialog()) {
if (fBD.ShowDialog() == DialogResult.OK)
selectedText.Text = fBD.SelectedPath;
}
}

with selectText = this.Controls[TextName] as TextBox;, you are trying to find button with replaced name which is not available in this case, and hence it returns null. This is logical mistake.
also string TextName = button.Name.Replace("btn_", "txt_"); does not replace button name, it just assigns replaced string to TextName.
The proper implementation would be
protected void button_Click(object sender, EventArgs e)
{
Button button = sender as Button;
folderBrowserDialog.ShowDialog();
button.Name = button.Name.Replace("btn_", "txt_");
TextBox selectText = new TextBox();
selectText = this.Controls[button.Name] as TextBox;
selectText.Text = folderBrowserDialog.SelectedPath;
}

How to create click event for dynamically created user controls in C#?

I'm creating a Windows Universal App which contains a ListView filled with User-Controls. User-Controls are added to ListView dynamically during runtime, based on the elements from the database.
public void ShowFavorites()
{
using (SQLite.Net.SQLiteConnection conn = new SQLite.Net.SQLiteConnection(new SQLite.Net.Platform.WinRT.SQLitePlatformWinRT(), (Application.Current as App).DBPath))
{
var Favorites = conn.Table<Favorites>();
lvFavorites.Items.Clear();
foreach (var fav in Favorites)
{
FavoriteItem favItem = new FavoriteItem();
favItem.Favorite = fav;
lvFavorites.Items.Add(favItem);
}
}
}
So how can i create an event that that triggers when the user-control is pressed?

When you create the control, all you need to do is simply link the control to a new event:
// Dynamically set the properties of the control
btn.Location = new Point((lbl.Width + cmb.Width + 17), 5);
btn.Size = new System.Drawing.Size(90, 23);
btn.Text = "Add to Table";
// Create the control
this.Controls.Add(btn);
// Link it to an Event
btn.Click += new EventHandler(btn_Click);
Then, when you (in this case) click on the newly added button, it will call your btn_Click method:
private void btn_Click(object sender, EventArgs e)
{
//do stuff...
}

I got it working even for items with diffrent text etc.
I gonna explain it based on a button beeing added to a panel.
You need to have a List<> in which you store the items, in this case buttons.
List<Button> BtList = new List<Button>();
and I also have a Panel in this case.
Panel PanelForButtons = new Panel();
Here is my code I hope it helps you:
void AddItemToPanel()
{
//Creating a new temporary item.
Button TempBt = new Button();
TempBt.Text = "Hello world!";
//Adding the button to our itemlist.
BtList.Add(TempBt);
//Adding the event to our button.
//Because the added item is always the last we use:
PanelForButtons.Controls.Add(BtList.Last());
BtList.Last().Click += MyButtonClicked;
}
And here is the event:
void MyButtonClicked(object sender, EventArgs e)
{
//First we need to convert our object to a button.
Button ClickedButton = sender as Button;
//And there we have our item.
//We can change the text for example:
ClickedButton.Text = "The world says: \"Hello!\"";
}

Change dynamic buttons text with textbox

Let me tell you what I want to do.
1.there are two button in my form.One of them let button when I click it.Another button finish to create button.
bool active = false;
private void button1_Click(object sender, EventArgs e)
{
active = true;
}
private void button2_Click(object sender, EventArgs e)
{
active = false;
}
2.I will create button with mousedown event I want to set location of this buttons with coordinate like this.
Button button_create;
private void frm_tr_MouseDown(object sender, MouseEventArgs e)
{
if (active)
{
button_create = new Button();
button_create.Location = new Point(e.X + 5, e.Y - 15);
button_create.Size = new Size(75, 30);
button_create.Text = "Button";
this.Controls.Add(button_create);
button_create.MouseClick += new MouseEventHandler(button_create_MouseClick);
}
}
3.I started mouseclickevent of my created button.When I click this created button I will create new form textbox and button.
TextBox button_text;
void button_create_MouseClick(object sender, MouseEventArgs e)
{
Form frm = new Form();
frm.Show();
button_text = new TextBox();
Button accept = new Button();
accept.Location = new Point(frm.Width / 2, frm.Height / 2);
frm.Controls.Add(button_text);
frm.Controls.Add(accept);
accept.MouseClick += new MouseEventHandler(accept_MouseClick);
}
4.I started mouseclickevent of my last created button.I want to change text of my first created button.
void accept_MouseClick(object sender, MouseEventArgs e)
{
button_create.Text = button_text.Text;
}
5.I will click button1 and I click anywhere of this form new button will create and I also click button2 to finish create new button.I can change my created button with textbox but
If I click button1 and I create a new one button I cant change text of previous created button How can I do that?

how to execute click event on dynamically created button in c#.net

I am trying to build an app, where user can select category and according to it displays its sub categories , these sub categories are buttons, which are dynamically created.
Now, as buttons are dynamically created so I am confuse how to write code under button_click event as I dont know how many subcategories are there.
So is there any way I can execute click event of a particular button , so that I can execute certain commands?
EDITED
This is the code that i tried
Button btnDynamicButton = new Button();
private void btnclick_Click(object sender, EventArgs e)
{
label2.Text = btnDynamicButton.Text;
}
private void btnappetizer_Click(object sender, EventArgs e)
{
groupBox2.Visible =false;
DataTable dt = new DataTable();
dt = itemmasterbl.SelectallrecordFromtblItem(btnappetizer.Text);
for (int i = 0; i < dt.Rows.Count; i++)
{
string name = "Appetizer" + DynamicButtonCount;
Button btnDynamicButton1 = new Button();
btnDynamicButton1.Name = name;
btnDynamicButton1.Text = name;
btnDynamicButton1.Size =
new System.Drawing.Size(150, 30);
btnDynamicButton1.Location =
new System.Drawing.Point(180, DynamicButtonCount * 30);
btnDynamicButton1.Click +=new EventHandler(btnclick_Click);<br>
Controls.Add(btnDynamicButton1);
DynamicButtonCount++;
btnDynamicButton = btnDynamicButton1;
}
}
Once I do this it creates three buttons according to number of values in itemmaster DB under appetizer, but once I click on any of the three buttons the label displays only last buttons text,because in last line I have :
btnDynamicButton = btnDynamicButton1;
Which will last buttons infos,but rather I want which ever button I press, label should display respective text. How can I achieve this.

you can put all your logic into one handler:
System.Windows.Forms.Button b = new System.Windows.Forms.Button();
b.Click += new EventHandler(b_Click);
//finally insert the button where it needs to be inserted.
...
void b_Click(object sender, EventArgs e)
{
MessageBox.Show(((System.Windows.Forms.Button)sender).Name + " clicked");
}
To your edit:
You are storing the reference for your button(s) inside the Field btnDynamicButton. Hence it always gets overwritten with the latest button you have created. You should not reference the button by using a field. The sender parameter of the click-handler contains the button element that has been clicked. See the code above: Simple cast sender to Button and you know which button has been clicked:
private void btnclick_Click(object sender, EventArgs e)
{
Button btn = (Button)sender
label2.Text = btn.Text;
}

Dynamic generation of buttons with their click event

I am doing following code to generate dynamic buttons with their click event.
protected void Button1_Click(object sender, EventArgs e)
{
for (int i = 0; i < int.Parse(TextBox1.Text); i++)
{
Button bt = new Button();
bt.Text = "ok";
bt.Click += new EventHandler(bt_click);
this.form1.Controls.Add(bt);
}
}
protected void bt_click(object sender, EventArgs e)
{
Label1.Text = "Clicked";
}
but i am not able to generate the click event of that dynamically generated button.
Can any one help me?

For ASP.NET to be able to execute your event, control which triggered it should also exist on your page after postback. What is going on with your code looks like this:
page has several buttons you placed in design mode
you click button which generates new buttons
page loads again and looks for button you clicked, in the page
button is found, asp looks for event handler and executes it
new dynamic buttons are added and events attached, page renders again
It was all ok up till now, now problem occurs
you click button which was added dynamically
page loads again and looks for button you clicked (so it can find it's handler)
button is not found because it is not created yet. it was created dynamically to be rendered, and it wasn't created after postback at stage where asp is looking for it
General rule is that if you're adding controls dynamically and you want them to trigger events, you should do it latest in Page_Load.
For more details please read ASP.NET Page Life Cycle Overview

My previous submission was on WinForms which I have deleted. Here is the one on asp.net
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
for (int i = 0; i < int.Parse(TextBox1.Text); i++)
{
CreateButton(i);
}
}
}
protected void Button1_Click(object sender, EventArgs e)
{
}
protected void bt_click(object sender, EventArgs e)
{
Button btn = sender as Button;
Label1.Text = btn.Text + " Clicked";
}
private void CreateButton(int id)
{
Button bt = new Button();
bt.Text = "ok" + id.ToString();
bt.Click += new EventHandler(bt_click);
bt.ID = "btn" + id.ToString();
this.Form.Controls.Add(bt);
}

You need to set the position of those new buttons, or they will cover each other.

I'm not sure if its your problem, but you might want to set the location property of eachbutton you add like:
bt.Location = new Point(25,i+55);

you need to add this code in either page load or page_init event of page. then only you can access it. How to add controls dynamically asp.net
protected void Page_Load()
{
for (int i = 0; i < int.Parse(textBox1.Text); i++)
{
Button bt = new Button();
bt.Text = "ok";
bt.Click += new EventHandler(bt_click);
this.Controls.Add(bt);
}
}