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Dynamically created button - onclick event not triggering

I have created a file upload control and a upload button in c# code as below: The controls are getting created and are shown in the UI- aspx
TableCell uploadCell = new TableCell();
uploadCell.ColumnSpan = 4;
tRow.Cells.Add(uploadCell);
FileUpload fu = new FileUpload();
fu.ID = "fu_" + BU + "_" + artifact.LookupValue + artifact.LookupId;
fu.AllowMultiple = false;
Button btnUpload = new Button();
btnUpload.ID = "btnUpload_" + BU + "_" + artifact.LookupValue + artifact.LookupId;
btnUpload.Text = "Upload";
btnUpload.Click += new EventHandler(this.btnUpload_Click);
PostBackTrigger trigger = new PostBackTrigger();
trigger.ControlID = btnUpload.ID;
uploadCell.Controls.Add(fu);
uploadCell.Controls.Add(btnUpload);
Up1.Triggers.Add(trigger);
private void btnUpload_Click(object sender, EventArgs e)
{
}
when I click on the upload button, the click event is not getting fired. I have attached a debug on the btnUpload_Click, but that is not hit.
How to trigger the click event for dynamically added control?

read the texts of run-time added textboxes

I have an application where the user can add any number of tabpages depending on what he/she needs. These tabpages have identical controls (textboxes and labels).
The controls on each tabpages are named like this: (on tabpage1 the controls are named: txtServer1, txtPort1, txtUser1, txtDbName1. if the user clicks the 'add another connection button' the application creates a second tabpage and the controls will be named: txtServer2, txtPort2, txtUser2, txtDbName2) and so on...
for example if the user have multiple tabpages to set-up:
the user clicks the 'add another connection' and the another tabpage with identical controls has been created and the user fills it up with appropriate data:
same thing goes here:
here's the code for dynamically added tabpage with controls:
//when 'add another connection' button is clicked
private void btnAddConnection_Click(object sender, EventArgs e)
{
string tabTitle = "Connection " + (tabControl1.TabCount + 1).ToString();
TabPage tabPage = new TabPage(tabTitle);
tabControl1.TabPages.Add(tabPage);
}
//when another tabpage has been added to tabcontrol
private void tabControl1_ControlAdded(object sender, ControlEventArgs e)
{
//control instances
TextBox txtServer = new TextBox();
TextBox txtPort = new TextBox();
TextBox txtUser = new TextBox();
TextBox txtDbName = new TextBox();
Label lblServer = new Label();
Label lblPort = new Label();
Label lblUser = new Label();
Label lblDbName = new Label();
tabControl1.SelectedTab = tabControl1.TabPages[tabControl1.TabCount - 1]; //select the newly addded tabpage
tabControl1.SelectedTab.BackColor = tabPage1.BackColor; //tabpage background color
//lblServer Properties
lblServer.Location = lblServer1.Location;
lblServer.Text = lblServer1.Text;
lblServer.ForeColor = lblServer1.ForeColor;
lblServer.Name = "lblServer" + tabControl1.TabCount.ToString();
//lblPort Properties
lblPort.Location = lblPort1.Location;
lblPort.Text = lblPort1.Text;
lblPort.ForeColor = lblPort1.ForeColor;
lblPort.Name = "lblPort" + tabControl1.TabCount.ToString();
//lblUser Properties
lblUser.Location = lblUser1.Location;
lblUser.Text = lblUser1.Text;
lblUser.ForeColor = lblUser1.ForeColor;
lblUser.Name = "lblUser" + tabControl1.TabCount.ToString();
//lblDbName Properties
lblDbName.Location = lblDbName1.Location;
lblDbName.Text = lblDbName1.Text;
lblDbName.ForeColor = lblDbName1.ForeColor;
lblDbName.Name = "lblDbName" + tabControl1.TabCount.ToString();
//txtserver properties
txtServer.Location = txtServer1.Location;
txtServer.Width = txtServer1.Width;
txtServer.Height = txtServer1.Height;
txtServer.Font = txtServer1.Font;
txtServer.Name = "txtServer" + tabControl1.TabCount.ToString();
//txtport properties
txtPort.Location = txtPort1.Location;
txtPort.Width = txtPort1.Width;
txtPort.Height = txtPort1.Height;
txtPort.Font = txtPort1.Font;
txtPort.Name = "txtPort" + tabControl1.TabCount.ToString();
//txtuser properties
txtUser.Location = txtUser1.Location;
txtUser.Width = txtUser1.Width;
txtUser.Height = txtUser1.Height;
txtUser.Font = txtUser1.Font;
txtUser.Name = "txtUser" + tabControl1.TabCount.ToString();
//txtdbname properties
txtDbName.Location = txtDbName1.Location;
txtDbName.Width = txtDbName1.Width;
txtDbName.Height = txtDbName1.Height;
txtDbName.Font = txtDbName1.Font;
txtDbName.Name = "txtUser" + tabControl1.TabCount.ToString();
//add controls to tabpage
tabControl1.SelectedTab.Controls.Add(lblServer);
tabControl1.SelectedTab.Controls.Add(lblPort);
tabControl1.SelectedTab.Controls.Add(lblUser);
tabControl1.SelectedTab.Controls.Add(lblDbName);
tabControl1.SelectedTab.Controls.Add(txtServer);
tabControl1.SelectedTab.Controls.Add(txtPort);
tabControl1.SelectedTab.Controls.Add(txtUser);
tabControl1.SelectedTab.Controls.Add(txtDbName);
}
When the user clicks the save button, I want the application to read each text in the textboxes (except for that url text) so that I can save it to a configuration file.
all I can think of is this
private void saveToolStripMenuItem_Click(object sender, EventArgs e)
{
string connection;
for (int i = 1; i <= tabControl1.TabCount; i++ )
{
connection = "server=" + txtServer[i].Text + ";port=" txtPort[i].Text + ";user=" + txtUser[i].Text + ";dbname=" + txtDbName[i];
//save to config file code goes here...
}
}
and I know this is not correct.
any solution for this? thanks :)

This is the simplest way you can try this just use below function to get text from control in tabpage
public string getValue(string controlName, TabPage selectedTab)
{
if (selectedTab.Controls.ContainsKey(controlName)){
TextBox selectedtb = (TextBox)selectedTab.Controls[controlName];
return selectedtb.Text;
}
else
return null;
}
and in your save code use it like below
string connection;
int i = 1;
TabControl.TabPageCollection pages = tabControl1.TabPages;
foreach (TabPage page in pages)
{
connection = "server=" + getValue("txtServer"+i,page) + ";port=" +getValue("txtPort"+i,page) + ";user=" + getValue("txtUser"+i,page) + ";dbname=" + getValue("txtDbName"+i,page);
i++;
//save to config file code goes here...
}

txtServer[i].Text it's true but You have not defined an array.
You can do it like this
//global
List<TextBox> txtServerList= new List<TextBox>();
private void tabControl1_ControlAdded(object sender, ControlEventArgs e)
{
txtServer.Location = txtServer1.Location;
txtServer.Width = txtServer1.Width;
txtServer.Height = txtServer1.Height;
txtServer.Font = txtServer.Font;
txtServer.Name = "txtServer" + tabControl1.TabCount.ToString();
txtServerList.Add(txtServer)
.
.
.
}
Finally
for (int i = 1; i <= tabControl1.TabCount; i++ )
{
connection=txtServerList.get(i).Text + ......
}

You could just loop over the controls and find the matching name, something like this:
foreach(var page in tabControl1.TabPages){
var server = ProcessControls(page.Controls, "txtServer");
//... continue with the others
}
private TextBox ProcessControls(Control ctrlContainer, string name)
{
foreach (Control ctrl in ctrlContainer.Controls)
{
if (ctrl.GetType() == typeof(TextBox))
{
if(ctrl.Name.StartsWith(name))
return (TextBox)ctrl;
}
}
}

You can use an ArrayList to store and access all dynamically added controls. Set a name for each dynamically added controls. It can be based on the size of ArrayList.
I will not show the exact systax of c#.
first
declare an ArrayList or List(Type Safe)
List<Button> buttons = new List<Button>();
We just created a storage for our buttons that will be added at runtime.
void your_event (some parameters) {
Button temp = new Button("Hello");
temp.Name="button_name";
YourMainPanel.Controls.add(temp);
//after creating your button add it to the parent container. of any control where you want this button to be added.
//you can also set the coordinates of the button if you like
//after creating the button we need to add it to our List so that we can
//access it later, since the value of the 'temp' will change after this
//event was invoked in the future.
buttons.add(temp);
}
There are several ways to get the items in List<T>. One is by using index.
void someMethod(some parameters) {
Button button = buttons.ElementAt(index);
}

Dynamic events in code

I have a radio buttons and one text box on a panel made dynamically . Now, I want to disable the text box when the second radio button is checked, means they are both connected. how can I make the event for it. I want to have the event working.
Thanks a lot in advanced.
this is my code which is not working:
Panel pnl = new Panel();
pnl.Name = "pnl_";
pnl.Size = new Size(630, 80);
RadioButton rd = new RadioButton();
rd.Name = "rd_" + dr[i]["Value_Name"].ToString();
rd.Text = dr[i]["Value_Name"].ToString();
rd.Location = new Point(i,i*2);
pnl.Controls.Add(rd);
TextBox txt = new TextBox();
txt.Name = "txt_" + Field_Name+"_"+dr[i]["Value_Name"].ToString();
txt.Size = new Size(171, 20);
txt.Text = Field_Name + "_" + dr[i]["Value_Name"].ToString();
txt.Location = new Point(20, 30);
pnl.Controls.Add(txt);
////// ???? ////////
rd.CheckedChanged += new EventHandler(eventTxt(txt));
void eventTxt(object sender,EventArgs e,TextBox txt)
{
RadioButton rd = (RadioButton)sender;
txt.Enabled = rd.Checked;
}

Use a lambda to close over the relevant variable(s):
rd.CheckedChanged += (s, args) => txt.Enabled = rd.Checked;
If you had more than a one line implementation, you could call out to a method accepting whatever parameters you've closed over, instead of including it all inline.

I would suggest to set the Tag of the radio button and get walk down the dependencies.
rd.Tag = txt;
In the event handler use this:
TextBox txt = (sender as Control).Tag as TextBox;
txt.Enabled = ...

you can use code given
rd.CheckedChanged += (s,argx) => txt.Enabled = rd.Checked;

Here's how you could create an event for it:
//if you are using Microsoft Visual Studio, the following
//line of code will go in a separate file called 'Form1.Design.cs'
//instead of just 'Form1.cs'
myTextBox.CheckChangedEventHandeler += new EventHandeler(checkBox1_CheckChanged); //set an event handeler
public void checkBox1_CheckChanged(object sender, EventArgs e) //what you want to happen every time the check is changed
{
if(checkBox1.checked == true) //replace 'checkBox1' with your check-box's name
{
myTextBox.enabled = false; //replace 'myTextbox' with your text box's name;
//change your text box's enabled property to false
}
}
Hope it helps!

Link button to display grid view asp.net dynamically

I have to display n grids, n is variable, then I dont know how many grids I'll have.
My problem is, I have to init this grids with Visible false and when click in a button show the grid specific for that button, then how can I link a button to a gridview?
My code that generate the grids:
foreach (List<DataRow> lst in grids)
{
dt = lst.CopyToDataTable();
GridView grv = new GridView();
grv.AlternatingRowStyle.BackColor = System.Drawing.Color.FromName("#cccccc");
grv.HeaderStyle.BackColor = System.Drawing.Color.Gray;
grv.ID = "grid_view"+i;
grv.Visible = false;
grv.DataSource = dt;
grv.DataBind();
Label lblBlankLines = new Label();
lblBlankLines.Text = "<br /><br />";
Label lblTipo = new Label();
string tipoOcorrencia = lst[0]["DESC_OCORRENCIA"].ToString();
tipoOcorrencia = CultureInfo.CurrentCulture.TextInfo.ToTitleCase(tipoOcorrencia);
int quantidade = lst.Count;
lblTipo.Text = tipoOcorrencia + ": " + quantidade;
LinkButton lkBtn = new LinkButton();
lkBtn.ID = "link_button"+i;
lkBtn.Text = "+";
place_grids.Controls.Add(lblBlankLines);
place_grids.Controls.Add(lkBtn);
place_grids.Controls.Add(lblTipo);
place_grids.Controls.Add(grv);
place_grids.DataBind();
i++;
}
Thanks in advance.

Modify your foreach loop as below.
private void GenerateControls()
{
int i = 0;
foreach (List<DataRow> lst in grids)
{
dt = lst.CopyToDataTable();
GridView grv = new GridView();
grv.AlternatingRowStyle.BackColor = System.Drawing.Color.FromName("#cccccc");
grv.HeaderStyle.BackColor = System.Drawing.Color.Gray;
grv.ID = "grid_view" + i;
//grv.Visible = false;//Commented as the grid needs be generated on client side, in order to make it visible from JavaScript/jQuery
grv.Attributes.Add("style", "display:none;");
grv.DataSource = dt;
grv.DataBind();
//Adding dynamic link button
LinkButton lnkButton = new LinkButton();
lnkButton.Text = "button " + i;
//lnkButton.Click += new EventHandler(lnkButton_Click);
lnkButton.ID = "lnkButton" + i;
lnkButton.OnClientClick = "ShowGrid('" + grv.ClientID + "');";
Label lblTipo = new Label();
lblTipo.Text = "text " + i;
lblTipo.ID = "lbl" + i;
tempPanel.Controls.Add(lblTipo);
tempPanel.Controls.Add(grv);
tempPanel.Controls.Add(lnkButton);
tempPanel.DataBind();
i++;
}
}
Then you will have to add a link button click event as below, if you want server side event to fire. (Un-comment the line where event handler is assigned to link button.)
protected void lnkButton_Click(Object sender, EventArgs e)
{
LinkButton lnkButton = (LinkButton)sender;
String index = lnkButton.ID.Substring(lnkButton.ID.Length - 1);
GridView grv = (GridView)tempPanel.FindControl("grid_view" + index);
grv.Visible = true;
}
You will need to add all dynamically added controls in the Page_Init event for maintaining their state. Refer below links can be useful.
Dynamically Created Controls losing data after postback
ViewState in Dynamic Control
Call method GenerateControls from Page_Init event as below.
protected void Page_Init(object sender, EventArgs e)
{
GenerateControls();
}
EDIT :
JavaScript function...
function ShowGrid(gridID) {
document.getElementById(gridID).style.display = ''
}
I have kept the server side click event as it is. But I have commented the line where the event handler is assigned to the link button.

Dynamic control and its Event

We are creating dynamic text boxes and buttons inside a grid for each row. Now we want to create click event for each button. To create button inside the grid in using ITemplate.
Code:
ImageButton imbtnAdd = new ImageButton();
imbtnAdd.ID = "imbtn" + columnName;
imbtnAdd.ImageUrl = "btn_add_icon.gif";
imbtnAdd.Width = 20;
container.Controls.Add(imbtnAdd);
Error:
I have used imbtnAdd.Click += new ImageClickEventHandler(imbtnAdd_Click); but it shows an error message
imbtnAdd_Click does not exist

ImageButton imbtnAdd = new ImageButton();
imbtnAdd.ID = "imbtn" + columnName;
imbtnAdd.ImageUrl = "btn_add_icon.gif";
imbtnAdd.Width = 20;
imbtnAdd.Click += imbtnAdd_Click;
container.Controls.Add(imbtnAdd);
// ...
private void imbtnAdd_Click(object sender, EventArgs e)
{
// handle event
}

Jrista's answer is correct.
Although, if you want to implement different handlers for all the buttons and you are using .Net 3.0 or above, you can use lambdas:
imbtnAdd.Click += (object sender, EventArgs e) =>
{
// Code handling code goes here...
};