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asp.net add link button dynamically click function

I'm trying to add a LinkButton dynamically
This is the html code:
<div id="resultDivText" runat="server">
<asp:PlaceHolder ID="PlaceHolder1" runat="server">
</asp:PlaceHolder>
</div>
This is the c# code
LinkButton lb = new LinkButton();
lb.Text = songName + "</br>"; //LinkButton Text
lb.ID = song.Key.ToString(); // LinkButton ID’s
lb.CommandArgument = Convert.ToString(song.Key);
lb.CommandName = Convert.ToString(song.Key);
lb.Click += new EventHandler(test_Click);
this.form1.Controls.Add(lb);
PlaceHolder1.Controls.Add(lb);
And this is the "test_Click" function
protected void test_Click(object sender, EventArgs e)
{
showAllSong("let it be");
}
When i run the code it's show me the linkButton list but when i click on it nothing happens.

Try this code ..
static bool enable = false;
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
DynamicButton();
}
else if (enable)
{
DynamicButton();
}
}
protected void btnBindMapping_Click(object sender, EventArgs e)
{
enable = true;
DynamicButton();
}
protected void DynamicButton()
{
LinkButton lb = new LinkButton();
lb = new LinkButton();
lb.Text = songName + "</br>"; //LinkButton Text
lb.ID = song.Key.ToString(); // LinkButton ID’s
lb.CommandArgument = Convert.ToString(song.Key);
lb.CommandName = Convert.ToString(song.Key);
lb.Click += new EventHandler(test_Click);
this.form1.Controls.Add(lb);
PlaceHolder1.Controls.Add(lb);
}
protected void test_Click(object sender, EventArgs e)
{
Response.Write("<script>alert('done'); </script>");
}

You code is fine ..it works as expected ..But change this line
this.form1.Controls.Add(lb);
to
this.Controls.Add(lb);
Note:It postback to your server not a client sided event

Since you use CommandName and CommandArgument in the LinkButton, you have to delegate a Command not a Click.
lb.Command += new CommandEventHandler(test_Click);
protected void test_Click(object sender, CommandEventArgs e)
{
Response.Write(e.CommandArgument + "<br>" + e.CommandName);
}
And remove the line this.form1.Controls.Add(lb);
And this is not clear from your question, but you have to create that button every time the page is loaded, and that includes a PostBack.

In give detail you have not mention. when this dynamic button is created.
Because that may create a issue.
If you call your c# code in page load event then it works.
LinkButton lb = new LinkButton();
lb = new LinkButton();
lb.Text = songName + "</br>"; //LinkButton Text
lb.ID = song.Key.ToString(); // LinkButton ID’s
lb.CommandArgument = Convert.ToString(song.Key);
lb.CommandName = Convert.ToString(song.Key);
lb.Click += new EventHandler(test_Click);
this.form1.Controls.Add(lb);
PlaceHolder1.Controls.Add(lb);
if that button create dynamically on oninit or onload event then it works.

Dynamic checkboxes in updatepanel staying checked

Within a site using a MasterPage, I have a page which has an UpdatePanel. Inside that, there is a ListBox which contains a list of users. There is also a dynamically generated list of checkboxes, which should have different values checked based upon which user is selected.
It works great the first time you select a user. However, when you select a second user, the original values remain - you see the checkboxes of both users checked.
.aspx
<asp:Content ID="BodyContent" ContentPlaceHolderID="MainContent" runat="server">
<h1>Access Database Security Controls</h1>
<asp:UpdatePanel ID="SecurityControls" runat="server">
<ContentTemplate>
<asp:ListBox ID="AccessUsers" runat="server" Rows="15" SelectionMode="Single" OnSelectedIndexChanged="AccessUsers_SelectedIndexChanged" AutoPostBack="true"></asp:ListBox>
<asp:PlaceHolder ID="SecurityRoles" runat="server"></asp:PlaceHolder>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
code behind
protected void Page_Load(object sender, EventArgs e)
{
LoadAllRoles();
}
protected void LoadAllRoles()
{
for (int i = 0; i < 4; i++)
{
Label lbl = new Label();
lbl.ID = "lbl_" + i.ToString();
lbl.Text = i.ToString() + " lbl text here";
SecurityRoles.Controls.Add(lbl);
CheckBox cb = new CheckBox();
cb.ID = "cb_" + i.ToString();
SecurityRoles.Controls.Add(cb);
SecurityRoles.Controls.Add(new LiteralControl("<br />"));
}
}
protected void AccessUsers_SelectedIndexChanged(object sender, EventArgs e)
{
Control page = Page.Master.FindControl("MainContent");
Control up = page.FindControl("SecurityControls");
Control ph = up.FindControl("SecurityRoles");
CheckBox cbRole = (CheckBox)ph.FindControl("cb_" + AccessUsers.SelectedValue);
if (cbRole != null)
cbRole.Checked = true;
}
I've tried doing cb.Checked = false; when I am creating the checkboxs, but even on the partial postbacks, the SecurityRoles placeholder control starts out empty.
How do I get the checkboxes to clear?

You can try to uncheck all other check-boxes before you check one.
foreach (Control c in ph.Controls)
{
if(c is CheckBox)
{
((CheckBox)c).Checked=false;
}
}

Dynamically created LinkButton OnClick Event not firing on PostBack

I am quite new to ASP and I have been stuck on an issue for about a week. The issue is probably something to do with the Asp Page Life Cycle but I am unable to find how this can be resolved. The issue is that skipto(..) is never called when I click the LinkButton (that were created on first Page Load), which means the LinkButtons are not rendered.
Sample Code below:
// Code Behind
protected void Page_Load(object sender, EventArgs e)
{
loadData();
if (!Page.IsPostBack)
{
skiptof();
}
}
public void loadData() {
// Loads from database
}
public void skipto(object sender, EventArgs e)
{
LinkButton btn = sender as LinkButton;
if (btn != null)
{
if (btn.CommandArgument != null && btn.CommandArgument != "0")
{
int currPage = 1;
int.TryParse(btn.CommandArgument, out currPage);
skiptof(currPage);
}
}
}
public void skiptof(int currPage = 1)
{
int lastPage = // calculate from LoadData()
string pageDisabled = "";
// pages
HtmlGenericControl ul = new HtmlGenericControl("ul");
while (pageCount <= lastPage)
{
// Disable the current page
pageDisabled = pageCount == currPage ? " class=\"disabled\"" : "";
HtmlGenericControl pagesli = new HtmlGenericControl("li");
if (pageDisabled != "")
{
pagesli.Attributes.Add("class", "disabled");
}
LinkButton pagesPageLink = new LinkButton();
pagesPageLink.Click += new EventHandler(skipto);
pagesPageLink.CommandArgument = pageCount.ToString();
pagesPageLink.Text = pageCount.ToString();
pagesli.Controls.Add(pagesPageLink);
ul.Controls.Add(pagesli);
pageCount += 1;
}
pagination.Controls.Add(ul);
}
// page
<asp:ScriptManager ID="ScriptManager1" runat="server"/>
<asp:UpdatePanel runat="server" id="UpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<div id="details" runat="server"></div>
<div class="pagination text-center" id="pagination" runat="server"></div>
</ContentTemplate>
</asp:UpdatePanel>

Your problem is:
You didn't bind the data again on postback, I've modified your code a little bit, there are several problems:
in the method skipof:
public void skiptof(int currPage = 1) {
//Clear the controls here then add them again
pagination.Controls.Clear();
int lastPage = // calculate from LoadData()
string pageDisabled = "";
HtmlGenericControl ul = new HtmlGenericControl("ul");
while (pageCount <= lastPage) {
// Disable the current page
pageDisabled = pageCount == currPage ? " class=\"disabled\"" : "";
HtmlGenericControl pagesli = new HtmlGenericControl("li");
if (pageDisabled != "") {
pagesli.Attributes.Add("class", "disabled");
}
LinkButton pagesPageLink = new LinkButton();
// you can directly assign the method to be called here, there is no need to create a new EventHandler
pagesPageLink.Click += PagesPageLink_Click;
pagesPageLink.CommandArgument = pageCount.ToString();
pagesPageLink.Text = pageCount.ToString();
pagesli.Controls.Add(pagesPageLink);
ul.Controls.Add(pagesli);
pageCount += 1;
}
pagination.Controls.Add(ul);
}
You didn't bind the data again in postback, so I modified it:
Page Load:
protected void Page_Load(object sender, EventArgs e) {
//Remove the Page.IsPostBack checking
skiptof();
}
Please take note that the controls you added dynamically will be cleared and you have to add it again on postback to avoid data lost.
Then you'll be able to get the value on PagesPageLink_Click event:
The whole sample is here:
http://pastie.org/10503291

Gridview dataBound add hyperlink to column data from code behind

Using grid view binding it from code behind:
I want to bind a particular column data into a hyper link so when it clicked it should do a download.
How to do that ?
Below is my code :
for (int i = 0; i <= tbl.Columns.Count - 1; i++)
{
Telerik.Web.UI.GridBoundColumn boundfield = new Telerik.Web.UI.GridBoundColumn();
if (tbl.Columns[i].ColumnName.ToString() == "Row")
{
LinkButton lkbtn = new LinkButton();
lkbtn.CommandName = i;
lkbtn.CommandArgument = "dwnld";
lkbtn.Font.Underline = true;
lkbtn.Text = tbl.Columns(i).ColumnName.ToString();
boundfield.DataField = tbl.Columns(i).ColumnName.ToString()
boundfield.HeaderText = tbl.Columns(i).ColumnName.ToString();
GridView2.MasterTableView.Columns.Add(boundfield);
}
}

Why not use grid template column with link button.
<telerik:GridTemplateColumn>
<ItemTemplate>
<asp:LinkButton ID="btnDownload" OnClick="btnDownload_Click" runat="server">Download Something</asp:LinkButton>
</ItemTemplate>
</telerik:GridTemplateColumn>
protected void btnDownload_Click(object sender, EventArgs e)
{
LinkButton lbBtn = sender as LinkButton;
GridDataItem item = (GridDataItem)(sender as LinkButton).NamingContainer;
// Use item to get other details
...
...
}

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.