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Dynamic controls dissapearing on postback

I am creating dynamic textboxes when clicking on a set of different radio button. Below is an example of two radio button onclick event.
protected void Checkbox1_CheckedChanged(object sender, EventArgs e)
{
string servicename = "service1";
if (checkbox1.Checked)
{
InputParameters.InputParameters aa= new InputParameters.InputParameters();
textbox = aa.GetInputFields(servicename);
for (int i=0;i<textbox.Count;i++)
{
// declare a textbox
TextBox CPDT = new TextBox();
CPDT.ID = servicename + i.ToString();
CPDT.CssClass = "form-control";
CPDT.EnableViewState = true;
Label lblCPD=new Label();
lblCPD.ID = "txtDynamiclbl" + servicename+ i.ToString();
lblCPD.CssClass= "form-control-label";
lblCPD.Text= textbox[i].ToString();
lblCPD.EnableViewState = true;
CPDPlaceHolder.Controls.Add(lblCPD);
CPDPlaceHolder.Controls.Add(CPDT);
//this.NumberOfControls++;
}
Button callSoap = new Button();
callSoap.ID = "txtDynamicSearch" + servicename;
callSoap.Text = "Search";
callSoap.CssClass = ".btn-info";
callSoap.CommandArgument = "test";
callSoap.Click += new EventHandler(btnsoap);
callSoap.EnableViewState = true;
CPDPlaceHolder.Controls.Add(callSoap);
}
else
{
}
}
protected void Checkbox2_CheckedChanged(object sender, EventArgs e)
{
string servicename = "service2";
if (checkbox2.Checked)
{
InputParameters.InputParameters aa = new InputParameters.InputParameters();
List<String> textbox = aa.GetInputFields("test1");
// textboxs.AddRange(textbox);
for (int i = 0; i < textbox.Count; i++)
{
// declare a textbox
TextBox CPDT = new TextBox();
CPDT.ID = servicename + i.ToString();
CPDT.CssClass = "form-control";
Label lblCPD = new Label();
lblCPD.ID = "txtDynamiclbl" + servicename + i.ToString();
lblCPD.CssClass = "form-control-label";
lblCPD.Text = textbox[i].ToString();
CPDPlaceHolder.Controls.Add(lblCPD);
CPDPlaceHolder.Controls.Add(CPDT);
}
Button callSoap = new Button();
callSoap.ID = "txtDynamicSearch" + servicename;
callSoap.Text = "Search";
callSoap.CssClass = ".btn-info";
callSoap.CommandArgument = "test1";
callSoap.Click += new EventHandler(btnsoap);
callSoap.EnableViewState = true;
CPDPlaceHolder.Controls.Add(callSoap);
}
else
{
}
}
The textboxes and search button appears as needed. The problem now is when i clicked on the search button a post back occur and all the controls are gone. I have been reading a lot about initialising the controls in page_preinit and i tried the code below.
protected void Page_PreInit(object sender, EventArgs e)
{
List<string> keys = Request.Form.AllKeys.Where(key => key.Contains("txtDynamic")).ToList();
int i = 1;
try
{
foreach (string key in keys)
{
TextBox CPDT = new TextBox();
CPDT.ID = "test" + i.ToString();
CPDT.CssClass = "form-control";
Label lblCPD = new Label();
lblCPD.ID = "txtDynamiclbl" + "test" + i.ToString();
lblCPD.CssClass = "form-control-label";
lblCPD.Text = textbox[i].ToString();
CPDPlaceHolder.Controls.Add(lblCPD);
CPDPlaceHolder.Controls.Add(CPDT);
i++;
}
}
catch
{
}
}
In the above function this line only returns the search button and not the texboxes. I am stuck on this issue.
List<string> keys = Request.Form.AllKeys.Where(key => key.Contains("txtDynamic")).ToList();
T

How to create a listbox dynamically in ASP.Net

protected override void OnInit(EventArgs e)
{
ListBox lst = new ListBox();
lst.Attributes["class"] = "cat-list";
lst.DataSource = cat.list(Convert.ToInt32(0));
lst.DataTextField = "catName";
lst.DataValueField = "catId";
lst.DataBind();
lst.AutoPostBack = true;
lst.SelectedIndexChanged += Lst_SelectedIndexChanged;
Panel pnl = new Panel();
pnl.Attributes["class"] = "col-sm-2 col-xs-12";
pnl.Controls.Add(lst);
categories.Controls.Add(pnl);
}
private void Lst_SelectedIndexChanged(object sender, EventArgs e)
{
ListBox listBox = (ListBox)sender;
ListBox lst = new ListBox();
lst.Attributes["class"] = "cat-list";
lst.DataSource = cat.list(Convert.ToInt32(listBox.SelectedValue));
lst.DataTextField = "catName";
lst.DataValueField = "catId";
lst.DataBind();
lst.AutoPostBack = true;
lst.SelectedIndexChanged += Lst_SelectedIndexChanged;
Panel pnl = new Panel();
pnl.Attributes["class"] = "col-sm-2 col-xs-12";
pnl.Controls.Add(lst);
categories.Controls.Add(pnl);
}
The first Listbox selectedindexchanged event working but second Listbox selectedindexchanged event not working. If I select a option on second listbox, second listbox lost.Just keep selected option on first listbox. What can I do about that? Please help me.

I hope that help you
Panel pnl = new Panel();
ListBox lst1 = new ListBox();
ListBox lst2 = new ListBox();
ListBox lst3 = new ListBox();
protected override void OnInit(EventArgs e)
{
lst1.Attributes["class"] = "cat-list";
lst1.AutoPostBack = true;
lst1.SelectedIndexChanged += Lst_SelectedIndexChanged;
lst2.Attributes["class"] = "cat-list";
lst2.AutoPostBack = true;
lst2.SelectedIndexChanged += Lst_SelectedIndexChanged;
lst2.Visible = false;
lst3.Attributes["class"] = "cat-list";
lst3.AutoPostBack = true;
lst3.SelectedIndexChanged += Lst3_SelectedIndexChanged;
lst3.Visible = false;
pnl.Attributes["class"] = "col-sm-2 col-xs-12";
pnl.Controls.Add(lst1);
pnl.Controls.Add(lst2);
pnl.Controls.Add(lst3);
categories.Controls.Add(pnl);
}
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
lst1.DataSource = cat.list(Convert.ToInt32(0));
lst1.DataTextField = "catName";
lst1.DataValueField = "catId";
lst1.DataBind();
}
}
private void Lst_SelectedIndexChanged(object sender, EventArgs e)
{
ListBox listBox = (ListBox)sender;
ListBox lst;
if (listBox == lst1)
lst = lst2;
else
lst = lst3;
lst.DataSource = cat.list(Convert.ToInt32(listBox.SelectedValue));
lst.DataTextField = "catName";
lst.DataValueField = "catId";
lst.DataBind();
lst.Visible = true;
}
private void Lst3_SelectedIndexChanged(object sender, EventArgs e)
{
//your code for third Listbox
}

sending data to event handler when the event is called programmatically

protected void Page_Load(object sender, EventArgs e)
{
Team T = new Team();
string[] TLeaders = T.GetAllTeamLeaders(Session["USER_EMAIL"].ToString(), Session["ProjectID"].ToString());
for (int i = 0; i < TLeaders.Length; i++)
{
System.Web.UI.HtmlControls.HtmlGenericControl createDiv =new System.Web.UI.HtmlControls.HtmlGenericControl("DIV");
createDiv.Style.Add(HtmlTextWriterStyle.BorderStyle, "Solid");
createDiv.Style.Add(HtmlTextWriterStyle.BorderColor, "lightblue");
createDiv.Style.Add(HtmlTextWriterStyle.BorderWidth, "1px");
createDiv.Style.Add(HtmlTextWriterStyle.Height, "100px");
createDiv.Style.Add(HtmlTextWriterStyle.Width, "1350px");
createDiv.Style.Add(HtmlTextWriterStyle.MarginTop, "20px");
createDiv.Style.Add(HtmlTextWriterStyle.BackgroundColor, "white");
DivRate.Controls.Add(createDiv);
Label LeaderName = new Label();
LeaderName.Text = TLeaders[i];
LeaderName.Style.Add("margin-left", "600px");
LeaderName.Style.Add("color","gray");
LeaderName.Style.Add("font-size","20px;");
LeaderName.Style.Add("margin-top", "10px");
LeaderName.Style.Add("position", "absolute");
createDiv.Controls.Add(LeaderName);
RadioButtonList Rate = new RadioButtonList();
ListItem bad = new ListItem();
ListItem fair = new ListItem();
ListItem good= new ListItem();
ListItem veryGood = new ListItem();
ListItem excellent = new ListItem();
bad.Value = "1";
bad.Text = "Bad";
fair.Value = "2";
fair.Text = "Fair";
good.Value = "3";
good.Text = "Good";
veryGood.Value = "4";
veryGood.Text = "Very Good";
excellent.Value = "5";
excellent.Text = "Excellent";
Rate.AutoPostBack = true;
Rate.Items.Add(bad);
Rate.Items.Add(fair);
Rate.Items.Add(good);
Rate.Items.Add(veryGood);
Rate.Items.Add(excellent);
Rate.Attributes.Add("onchange", "return LeaderName('"+TLeaders[i]+"');");
Rate.SelectedIndexChanged += new EventHandler(CheckChange("s"));
Rate.RepeatColumns=5;
Rate.Width = 10;
Rate.Height = 10;
Rate.CssClass = "RateClass";
createDiv.Controls.Add(Rate);
}
}
so in this code I create a div and I place inside it a label and a Radio Button List however what i want to do is to create an event handler and send a data to it when i call it i call it like this:
Rate.SelectedIndexChanged += new EventHandler(CheckChange("s"));
and this is the event handler:
protected void CheckChange(string s)
{
ScriptManager.RegisterStartupScript(Page, typeof(Page), "", "fun('" + s + "')", true);
}
It give me an error "method name expected" when I send the data like this
any solution?

Stay open context menu after click

I've got datagrid with context menu. It is initialized programatically:
contextMenu = new ContextMenu();
foreach (var col in this.Columns)
{
var checkBox = new MenuItem()
{
Header = col.Header
};
Binding myBinding = new Binding("Visibility");
myBinding.Mode = BindingMode.TwoWay;
myBinding.Converter = new IsCheckedToVisibilityConverter();
checkBox.DataContext = col;
checkBox.SetBinding(MenuItem.IsCheckedProperty, myBinding);
checkBox.Click += checkBox_Click;
checkBox.Checked += checkBox_Checked;
checkBox.Unchecked += checkBox_Unchecked;
contextMenu.Items.Add(checkBox);
}
It works great, but i would like to stay open context menu after check\uncheck menuitems. Any ideas ?

After adding checkBox.StaysOpenOnClick = true; works as expected
contextMenu = new ContextMenu();
foreach (var col in this.Columns)
{
var checkBox = new MenuItem()
{
Header = col.Header
};
//binding
Binding myBinding = new Binding("Visibility");
myBinding.Mode = BindingMode.TwoWay;
myBinding.Converter = new IsCheckedToVisibilityConverter();
checkBox.DataContext = col;
checkBox.SetBinding(MenuItem.IsCheckedProperty, myBinding);
checkBox.Click += checkBox_Click;
checkBox.Checked += checkBox_Checked;
checkBox.Unchecked += checkBox_Unchecked;
checkBox.StaysOpenOnClick = true;
contextMenu.Items.Add(checkBox);
}

You can try:
private bool close= true;
private void CheckBox1_CheckedChanged(Object sender, EventArgs e)
{
close= false;
}
private void contextMenu_Closing(object sender, ToolStripDropDownClosingEventArgs e)
{
e.Cancel = !close;
CloseContextMenu = true;
}

Update DataGrid inside AJAX accordion

I have an AJAX accordion from the ajax control toolkit on a page with a datagrid inside on of the panels. I have a custom itemtemplate for the one column to create a multiline textbox when I click edit on the row. When I click update on the row, the original content of the textbox gets rendered into the textbox. It is supposed to update and go back to the literal not the textbox. When I put the DataBind() into a !IsPostBack, it doesnt get rendered when I click on the accordion pane. Any ideas?
Code:
protected void Page_Load(object sender, EventArgs e)
{
announ.HeaderStyle.CssClass = "header";
announ.Width = Unit.Percentage(100);
announ.GridLines = GridLines.None;
announ.AutoGenerateColumns = false;
announ.CellPadding = 10;
announ.CellSpacing = 0;
announ.HorizontalAlign = HorizontalAlign.Center;
announ.HeaderStyle.Font.Bold = true;
announ.EnableViewState = false;
announ.AlternatingItemStyle.BackColor = System.Drawing.Color.GhostWhite;
//announ.DeleteCommand += AnnounDeleteCommand;
announ.EditCommand += announ_EditCommand;
announ.UpdateCommand += announ_UpdateCommand;
announ.CancelCommand += announ_CancelCommand;
announ.DataKeyField = "id";
var tc1 = new TemplateColumn
{
HeaderTemplate = new
DataGridTemplate(ListItemType.Header, "Announcement"),
ItemTemplate = new DataGridTemplate(ListItemType.Item, "announcement_text"),
EditItemTemplate = new
DataGridTemplate(ListItemType.EditItem, "announcement_text")
};
var editColumn = new EditCommandColumn
{
ButtonType = ButtonColumnType.PushButton,
HeaderText = "Edit",
EditText = "Edit",
UpdateText = "Update",
CancelText = "Cancel"
};
var dateColumn = new BoundColumn {HeaderText = "Posted On", DataField = "date", ReadOnly = true};
var expirationColumn = new BoundColumn {HeaderText = "Expiration Date", DataField = "expiration_date"};
announ.Columns.Add(tc1);
announ.Columns.Add(dateColumn);
announ.Columns.Add(expirationColumn);
announ.DataSource = myAnnouncements;
announ.DataBind();
var deptMgtaccord = new Accordion
{
ID = "deptMgtaccord",
HeaderCssClass = "accordion-header",
HeaderSelectedCssClass = "accordion-headerSelected",
AutoSize = AutoSize.None,
SelectedIndex = 0,
FadeTransitions = true,
TransitionDuration = 250,
FramesPerSecond = 40,
RequireOpenedPane = false,
SuppressHeaderPostbacks = true
};
if (IsPostBack)
{
deptMgtaccord.SelectedIndex = selected;
}
var announcementPane = new AccordionPane {ID = "announcementPane"};
announcementPane.HeaderContainer.Attributes.Add("onmouseover", "this.style.backgroundColor='#e3e2e2';");
announcementPane.HeaderContainer.Attributes.Add("onmouseout", "this.style.backgroundColor='#ffffff';");
announcementPane.HeaderContainer.Controls.Add(new LiteralControl("Announcements >>"));
announcementPane.ContentContainer.Controls.Add(announ);
deptMgtaccord.Panes.Add(announcementPane);
var statsPane = new AccordionPane {ID = "statsPane"};
statsPane.HeaderContainer.Attributes.Add("onmouseover", "this.style.backgroundColor='#e3e2e2';");
statsPane.HeaderContainer.Attributes.Add("onmouseout", "this.style.backgroundColor='#ffffff';");
statsPane.HeaderContainer.Controls.Add(new LiteralControl("Statistics >>"));
statsPane.ContentContainer.Controls.Add(new LiteralControl("Stats"));
deptMgtaccord.Panes.Add(statsPane);
ph1.Controls.Add(deptMgtaccord);
}
protected void announ_CancelCommand(object source, DataGridCommandEventArgs e)
{
announ.EditItemIndex = -1;
announ.DataBind();
}
protected void announ_UpdateCommand(object source, DataGridCommandEventArgs e)
{
var dc = new MTCDataDataContext();
var announText = (TextBox) e.Item.Cells[1].Controls[1];
int announId = (int)announ.DataKeys[e.Item.ItemIndex];
var currentAnnoun = (from a in dc.announcements
where a.id == announId
select a).SingleOrDefault();
currentAnnoun.announcement_text = announText.Text;
dc.SubmitChanges();
announ.EditItemIndex = -1;
announ.DataBind();
}
protected void announ_EditCommand(object source, DataGridCommandEventArgs e)
{
announ.EditItemIndex = e.Item.ItemIndex;
announ.DataBind();
}
public class DataGridTemplate : ITemplate
{
ListItemType templateType;
string columnName;
public DataGridTemplate(ListItemType type, string colname)
{
templateType = type;
columnName = colname;
}
public void InstantiateIn(Control container)
{
Literal lc = new Literal();
TextBox tb = new TextBox();
switch (templateType)
{
case ListItemType.Header:
lc.Text = "<B>" + columnName + "</B>";
container.Controls.Add(lc);
break;
case ListItemType.Item:
lc.DataBinding += lc_DataBinding;
container.Controls.Add(lc);
break;
case ListItemType.EditItem:
tb.TextMode = TextBoxMode.MultiLine;
tb.Rows = 6;
tb.Columns = 57;
tb.DataBinding += tb_DataBinding;
container.Controls.Add(tb);
break;
case ListItemType.Footer:
lc.Text = "<I>" + columnName + "</I>";
container.Controls.Add(lc);
break;
}
}
void tb_DataBinding(object sender, EventArgs e)
{
TextBox tb = (TextBox)sender;
DataGridItem row = (DataGridItem)tb.NamingContainer;
tb.ID = "txt_" + row.ItemIndex;
tb.Text = DataBinder.Eval(row.DataItem, columnName).ToString();
}
void lc_DataBinding(object sender, EventArgs e)
{
Literal lc = (Literal)sender;
DataGridItem row = (DataGridItem)lc.NamingContainer;
lc.ID = "txt_" + row.ItemIndex;
lc.Text = DataBinder.Eval(row.DataItem, columnName).ToString();
}
}

You need to add your dynamic controls in PreInit on every request in order for the controls to get back into the ControlTree and raise events.
Page Event:
PreInit
Typical Use:
Raised after the start stage is complete and before the initialization stage begins.
Use this event for the following:
Check the IsPostBack property to determine whether this is the first
time the page is being processed. The
IsCallback and IsCrossPagePostBack
properties have also been set at this
time.
Create or re-create dynamic controls.
Set a master page dynamically.
Set the Theme property dynamically.
Read or set profile property values.
Note: If the request is a postback, the values of the controls have not yet been restored from view state. If you set a control property at this stage, its value might be overwritten in the next event.