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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

C# Drop Down List Not Trigger index changing

I select one value on the ddl , and it does not show the products in the page. The selected value remains binded but the page is blank.
Also , if I just call function getCat() without using if(!ispostback). When i load the page the drop down list is stuck on the first value , but it shows the products in page.
Drop Down List:
<asp:dropdownlist runat="server" id="ddcateg" AutoPostBack="true" onselectedindexchanged="Ddcateg_SelectedIndexChanged"></asp:dropdownlist>
This is the implementation:
protected void Page_Load(object sender, EventArgs e)
{
//afisare();
if (!IsPostBack)
{
getCateg();
}
}
public void getCateg()
{
ProdusTipModel model = new ProdusTipModel();
FarmacieEntities db = new FarmacieEntities();
var lizt = (from c in db.ProdusTips select c).ToList();
ddcateg.DataSource = lizt;
ddcateg.DataValueField = "ID";
ddcateg.DataTextField = "Name";
ddcateg.DataBind();
ddcateg.SelectedIndexChanged += Ddcateg_SelectedIndexChanged;
}
public void afisare2(List<Produ> z)
{
ProdusModel mdl = new ProdusModel();
foreach (var produs in z)
{
Panel produsePnl = new Panel();
ImageButton imageButton = new ImageButton();
produsePnl.BorderColor = Color.AliceBlue;
Label lblNume = new Label();
Label lblPret = new Label();
produsePnl.BorderStyle = BorderStyle.Groove;
produsePnl.BorderColor = Color.LightSkyBlue;
imageButton.ImageUrl = "~/Img/Produse/" + produs.Image;
imageButton.CssClass = "imgProdus";
imageButton.PostBackUrl = "~/Pages/PaginaProdus.aspx?id=" + produs.ID;
lblNume.Text = produs.Name;
lblNume.CssClass = "numeProd";
lblPret.Text = produs.Price + "lei";
lblPret.CssClass = "produsPret";
produsePnl.Controls.Add(imageButton);
produsePnl.Controls.Add(new Literal { Text = "<br /" });
produsePnl.Controls.Add(lblNume);
produsePnl.Controls.Add(new Literal { Text = "<br /" });
produsePnl.Controls.Add(lblPret);
pnlProduse.Controls.Add(produsePnl);
}
}
private void Ddcateg_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList selectedList = (DropDownList)sender;
int selectedLit = Convert.ToInt32(selectedList.SelectedValue);
ProdusModel mdl = new ProdusModel();
List<Produ> list = mdl.GetProdCateg(selectedLit).ToList();
afisare2(list);
}

Your problem could be that your code behind method is private:
private void Ddcateg_SelectedIndexChanged(object sender, EventArgs e)
Try making it protected or public so it can be seen by the aspx page.

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.

Gridview Edit/Update is not working?

Here i am updating the gridview value but the value is not updating..TextBox txtID,TextBox txtName,TextBox txtAge retains the older value only and the value is not getting updated..Can anyone tel me like what am i doing wrong here
Here is my code
protected void gvTemp_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
CreateDataSkeletton(Convert.ToInt16(Session["intTabIndex"]));
GridViewRow row = (GridViewRow)gvTemp.Rows[e.RowIndex];
int autoid = Int32.Parse(gvTemp.DataKeys[e.RowIndex].Value.ToString());
int id = Convert.ToInt32(gvTemp.DataKeys[e.RowIndex].Values[0].ToString());
activeTabIndex = Convert.ToInt16(Session["activeTabIndex"]);
TextBox txtID = ((TextBox)gvTemp.Rows[e.RowIndex].FindControl("txtId"));
TextBox txtName = (TextBox)gvTemp.Rows[e.RowIndex].FindControl("txtName");
TextBox txtAge = (TextBox)gvTemp.Rows[e.RowIndex].FindControl("txtAge");
dataSetInSession.Tables["Days" + activeTabIndex.ToString()].Rows[e.RowIndex]["ID"] = txtID.Text;
dataSetInSession.Tables["Days" + activeTabIndex.ToString()].Rows[e.RowIndex]["Name"] = txtName.Text;
dataSetInSession.Tables["Days" + activeTabIndex.ToString()].Rows[e.RowIndex]["Age"] = txtAge.Text;
gvTemp.DataSource = dataSetInSession.Tables["Days" + activeTabIndex.ToString()];
gvTemp.DataBind();
gvTemp.EditIndex = -1;
}
and
private void CreateDataSkeletton(int intTabIndex)
{
dataSetInSession = new DataSet();
Session["intTabIndex"] = intTabIndex;
if (Session["dataSetInSession"] != null)
{
dataSetInSession = (DataSet)Session["dataSetInSession"];
}
if (dataSetInSession.Tables["Days" + intTabIndex].Rows.Count > 0)
{
gvTemp.DataSource = dataSetInSession.Tables["Days" + intTabIndex];
gvTemp.DataBind();
}
else
{
gvTemp.DataSource = dataSetInSession.Tables["Days"];
gvTemp.DataBind();
}
temp.Controls.Add(gvTemp);
}
Any suggestion??
EDIT(1):
protected void Page_Init(object sender, EventArgs e)
{
if (!IsPostBack)
{
AddDataTable();
}
dataSetInSession = new DataSet();
if (Session["dataSetInSession"] != null)
{
dataSetInSession = (DataSet)Session["dataSetInSession"];
}
if (Session["dynamicTabIDs"] != null)
{
//if dynamicTabIDs are in session, recreating the Tabs
//that are associated with the Tab IDs
//and adding them to the TabContainer that will contain
//all of the dynamic tabs.
//retrieving the tab IDs from session:
dynamicTabIDs = (List<string>)Session["dynamicTabIDs"];
if (TabContainerContent.ActiveTabIndex == -1)
{
TabContainerContent.ActiveTabIndex = Convert.ToInt16(Session["intTabIndex"]);
}
CreateDataSkeletton(Convert.ToInt16(Session["intTabIndex"]));
//looping through each TabID in session
//and recreating the TabPanel that is associated with that tabID
foreach (string tabID in dynamicTabIDs)
{
//creating a new TabPanel that is associated with the TabID
AjaxControlToolkit.TabPanel tab = new AjaxControlToolkit.TabPanel();
//TabContainerContent.ActiveTabIndex = tab;
//Setting the ID property of the TabPanel
tab.ID = tabID;
//setting the TabPanel's HeaderText
tab.HeaderText = "Days " + (TabContainerContent.Tabs.Count + 1).ToString();
//creating a Label to add to the TabPanel...at this point you'll have to
//create whatever controls are required for the tab...
Label tabContent = new Label();
//Giving the Label an ID
tabContent.ID = "lbl_tab_" + TabContainerContent.Tabs.Count.ToString();
//Setting the Label's text
tabContent.Text = "Tab " + (TabContainerContent.Tabs.Count + 1).ToString();
//Adding the Label to the TabPanel
tab.Controls.Add(tabContent);
//Adding the TabPanel to the TabContainer that contains the dynamic tabs
TabContainerContent.Tabs.Add(tab);
}
}
else
{ //Creating a new list of dynamicTabIDs because one doesn't exist yet in session.
dynamicTabIDs = new List<string>();
}
}
protected void Page_Load(object sender, EventArgs e)
{
}

Read Page Life Cycle
And you will get, that if you want to bind in code-behind, you should do it in Init Event, other wise there are no events will fire.

It seems to be Page.IsPostback problem.Need to add Page.IsPostback property in your page_load like
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
// Put your code inside that.
}
}
Actually your control is getting new value but when you click for updation then it calls old value from page_load.So try to put Page.IsPostback into your page_load event,Just like i mentioned.
I hope it helps.

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.