There is a problem to find a dynamic control on a page. The dynamic control is created every time when a user press a button. The button calls the following JavaScript function and create a new components.
<script type="text/javascript">
var uploadCount = 1;
function addFileInput(fName) {
var only_file_name = fName.replace(/^.*[\\\/]/, '');
var $div = $('<div />', {runat: 'server'});
var $cbox = $('<input />', { type: 'checkbox', id: 'attachement' + uploadCount, value: fName, checked: "true", runat: 'server'}).addClass;
var $label = $('<label />', { 'for': 'attachement' + uploadCount, text: only_file_name });
$div.append($cbox);
$div.append($label);
$('#newAttachment').append($div);
$("#uploadCountValue").prop("value", uploadCount);
uploadCount++;
}
</script>
newAttachment is DIV section on the page.
<div id="newAttachement" runat="server" />
The DIV section is situated inside section. The problem is when a user presses the button on the form I can't find the dynamic created components. The following code shows how I try to find the components:
for (int i = 1; i <= Convert.ToInt32(uploadCountValue.Value); i++)
{
if (RecursiveFind(newAttachement, "attachement" + i) != null)
{
... to do something
}
}
public Control RecursiveFind(Control ParentCntl, string NameToSearch)
{
if (ParentCntl.ID == NameToSearch)
return ParentCntl;
foreach (Control ChildCntl in ParentCntl.Controls)
{
Control ResultCntl = RecursiveFind(ChildCntl, NameToSearch);
if (ResultCntl != null)
return ResultCntl;
}
return null;
}
I have detected that Controls count value is always zero in spite of there are dynamic components there.
I would be happy to get any help from us. Thanks.
to find the controls created in the client-end you can't search them in the Page.Controls collection instead try to look for them in the Request.Form[] array
you are creating the dynamic controls in javascript? i.e. you are creating html elements in javascript. It won't matter even if you put a runat="server" attribute in there, because it is still at the client-end. That would not be a part of the viewstate bag, so not populated in the controls collection.
you need to change your logic. create dynamic control in code-behind on button postback.
Related
I've read a few articles regarding getting values back from a modal popup in an ASP .NET page, but they all seem to use JavaScript to accomplish this which isn't really want I want to do if possible.
I have a web user control which has a repeater that I populate from a list into a table. Each row has a link button which has a redirect url with a value as a query string.
Then I have another web user control which is just a link button with a panel and the repeater web user control that once clicked shows the actual modal popup.
Is it possible to get a value from the web user control once the link button on the repeater is clicked without having to redirect to the same page? I basically want to click on the link, show the modal and once closed, want to access the value.
I'm populating the repeater with the links as follows:
string linkUrl = "";
string action = "";
if (Request.QueryString["action"] != null)
{
action = Request.QueryString["action"];
switch (action)
{
case "SetupCompany":
{
linkUrl = "<a href=CreateCompanies.aspx?companyId=";
break;
}
case "ViewCompany":
{
linkUrl = "<a href=ViewCompany.aspx?companyId=";
break;
}
}
}
CompaniesBusinessManager mgr = new CompaniesBusinessManager();
var companies = mgr.GetCompanies(txtCompanyName.Text, txtRegistrationNumber.Text);
if (linkUrl != "")
{
foreach (var c in companies)
{
c.Name = linkUrl + c.Id.ToString() + "&action=" + action + ">" + c.Name + "</a>";
}
}
rptrCompanies.DataSource = companies;
rptrCompanies.DataBind();
if you don't want the page to be redirected, you will need to use javascript.
There is now way you can pass values from different controls without going back to the server.
In case you keep it without the javascript:
I think you need to pass values from one user control to another. I used to accomplish this by firing reachable events between them.
For example:
in your parent view:
<uc:YourUserControl runat="server" ID="UserControl_Test"
OnYourCustomAction="UserControl_YourUserControl_YourCustomAction" />
In your user control:
public event EventHandler<CustomActionEventArgs> YourCustomAction;
also in the same user control create a public trigger method to be access from others usercontrols
public void TriggerCustomActoinEvent(CustomActionEventArgs EventArgs)
{
if (this.YourCustomAction!= null)
{
this.YourCustomAction(this, EventArgs);
}
}
Hope this help, in on my way to home this was from my mind!
Without a page postback or JavaScript it not really possible. If you are using modal popups you are already using JS, so why not just get the value in JS? You could setup an event handler for all repeater buttons and if they are loaded via ajax use something like this to attach the event handler:
$(document).on('click', '.repeaterButton', function(e) {
var valueOfBtnClicked = $(this).val();
// Do something else
});
I'm writing a for loop that displays a list of links with some chartfx display. The chartfx needs an sqlDataSource. I'm trying to give the unique ID each time the for loop does one iteration but I can not pass it a value or function. Example below in my code.
getSQLID() is just a function that returns a string which I want to be my ID. This is all done on the aspx page and the function is in the .cs . Any help would be really appreciated thank you.
//name of the contentplace holder on the aspx page
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server" >
//code behind
Control ctrl = LoadControl("WebUserControl.ascx");
Control placeHolderControl = this.FindControl("Content2");
Control placeHolderControl2 = this.FindControl("ContentPlaceHolder1");
ctrl.ID = "something";
if (placeHolderControl != null)
placeHolderControl.Controls.Add(ctrl);
if (placeHolderControl2 != null)
placeHolderControl2.Controls.Add(ctrl);
First of all, recall that server controls declared in the designer like this are attached to your class at compile time. So it doesn't make sense to try to create multiple instances in a loop at runtime, and that's why the values in e.g. the Id tag have to be known at compile time.
One alternative is to create them in the code behind, with something like:
for (int i=0; i<2; ++i)
{
var chart = new Chart();
chart.Id = "chartId" + i;
chart.DataSourceId = "srcid" + i;
var src = new SqlDataSource();
src.Id = "srcid" + i;
Controls.Add(chart); // either add to the collection or add as a child of a placeholder
Controls.Add(src);
}
In your case converting all of those declarative properties to the code behind can be a bit of work (though it is possible). An alternative is to make a user control (ascx) that contains the markup that's now in your aspx page. You would instantiate the controls in your code behind with something like:
for (int i=0; i<2; ++i)
{
var ctrl = LoadControl("~/path/to/Control.ascx");
ctrl.Id = "something_" + i;
Controls.Add(ctrl); // again, either here or as a child of another control
// make the src, hook them up
}
I currently use a hidden input field that is assigned the value of the tab that has just been selected, via javascript, like so:
function onTabSelecting(sender, args) {
var tab = args.get_tab(); //get selected tab
document.getElementById("MainContent_hdnPreviousTab").value = tab.get_text(); //assign value to hidden field
if (tab.get_pageViewID()) { //ignore
tab.set_postBack(false);
}
}
I then use this assigned value when the page is returned to, on client-side (ajax) PageLoad() event:
<script type="text/javascript" language="javascript">
var runOnce = false;
function pageLoad() {
if (!runOnce) {
var lastTab = document.getElementById("<%= hdnPreviousTab.ClientID %>");
if (lastTab.value) {
if (tabStrip) {
var tab = tabStrip.findTabByText(lastTab.value);
if (tab) {
tab.click();
}
}
}
runOnce = true;
}
}
</script>
Currently in IE this works fine (I know right?), the value that was previously set in javascript is still there and i am able to lcoate the tab that the user left the page on. However in FF, Chrome, etc. i have no such luck. The hidden field is returned to it's empty state (value = "") regardless of utilising viewstate or not.
Very curious as to whether anyone has an alternative method that would be appropriate in this situation. Please let me know if this is unclear.
Many thanks.
You could use localstorage.
localStorage.setItem('tab', value);
I am using a treeview control. I am buliding the tree dynamically. sometimes the tree becomes larger and the down scroll bar is need to see the entire tree.
user can select a node from the tree. if one node is selected ,i change the color of the node from server side.
my problem is that if a user selected a node which is bottom in the tree(means, the user used the down scrollbar to see that node), after postback it shows the top of the tree.to see the selected node the user need to use the down scroll bar.
I need to show the selected node after postback. How can I do this?
I am using c# and asp.net
With help of jquery we can send the selected node id to the query string and on document.ready we can read back and highlight that node.
Have a look on the code:
Code behind onclick code:
public void TreeView1_OnClick(Object sender, EventArgs e)
{
ScriptManager.RegisterStartupScript(
Page,
Page.GetType(),
"HighlightSelectedNode",
"HighlightSelectedNode();",
true
);
}
and the javascript:
<script type="text/javascript" language="javascript">
function HighlightSelectedNode() {
var selectedNodeID = $('#<%= TreeView1.ClientID %>_SelectedNode').val();
if (selectedNodeID != "") {
document.location.href = "http://" + window.location.host
+ window.location.pathname
+ "?Node=" + selectedNodeID;
return false;
} else {
// alert("Not found");
}
}
// Highlight active node on pageload.
$(document).ready(function () {
var querystring = location.search.replace('?', '').split('&');
var queryObj = {};
for (var i = 0; i < querystring.length; i++) {
var name = querystring[i].split('=')[0];
var value = querystring[i].split('=')[1];
queryObj[name] = value;
}
var nodeID = queryObj["Node"];
$('#' + nodeID).css({ 'background-color': '#888'});
});
</script>
You can use update panel to work around this issue.
I have masterpage with content place holder. i have contentpage which is using master page . in all my content page i need to default focus on the text box so that the user can directly type in text box instead moving the mouse over the textbox. in some page there is no text box so that i donnot nnet keep default focus over there
Is there any way i can do it in my master page once and can reuse that in all my content page
thank you
try using this...
((TextBox)Master.FindControl("txtRequiredFocus")).Focus();
You could include this in your master page's load event:
// if the ID is constant you can use this:
/*TextBox textBox = (TextBox)Page.Controls[0]
.FindControl("ContentPlaceHolder1")
.FindControl("myTextBox");
*/
// this will look for the 1st textbox without hardcoding the ID
TextBox textBox = (TextBox)Page.Controls[0]
.FindControl("ContentPlaceHolder1")
.Controls.OfType<TextBox>()
.FirstOrDefault();
if (textBox != null)
{
textBox.Focus();
}
This would match up with a content page that has the following markup:
<asp:Content ID="Content" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<asp:TextBox ID="myTextBox" runat="server" />
</asp:Content>
EDIT: if LINQ isn't an option then you can use this instead:
foreach (Control control in Page.Controls[0].FindControl("ContentPlaceHolder1").Controls)
{
if (control is TextBox)
{
((TextBox)control).Focus();
break;
}
}
Indiscriminate JavaScript approach to selecting the first valid input field on a page:
function SelectFirstInput() {
var bFound = false;
for (f = 0; f < document.forms.length; f++) {
// for each element in each form
for (i = 0; i < document.forms[f].length; i++) {
// if it's not a hidden element
if (document.forms[f][i].type != "hidden") {
// and it's not disabled
if (document.forms[f][i].disabled != true) {
// set the focus to it
document.forms[f][i].focus();
var bFound = true;
}
}
// if found in this element, stop looking
if (bFound == true)
break;
}
// if found in this form, stop looking
if (bFound == true)
break;
}
}
<script language="javascript" type="text/javascript" >
window.onload=function(){
var t= document.getElementById('<%=TextBox1.clientID %>');
t.focus();
}
</script>
If you use jQuery, a possible solution is:
Give the textbox you want to set focus to a special class. "focus" works well for this purpose.
Write code such as the following in your master page or included by your master page in a js script file:
$(document).ready
(
function()
{
//get an array of DOM elements matching the input.focus selector
var focusElements = $("input.focus").get();
//if a focus element exists
if(focusElements.length > 0)
{
focusElements[0].focus();
}
}
);
A similar approach using vanilla JavaScript would be to tag the textbox with a special attribute. Let's use focus.
window.onload = function()
{
//get all input elements
var inputElements = document.getElementsByTagName("input");
var elementToFocus = null;
for(var i = 0; i < inputElements.length; ++i)
{
var focusAttribute = inputElements[i].getAttribute("focus");
if(focusAttribute)
{
elementToFocus = inputElements[i];
break;
}
}
if(elementToFocus)
{
elementToFocus.focus();
}
};
Control masterC =
Page.Master.FindControl("ContentPlaceHolder1");
TextBox TextBox1 =
masterC.FindControl("TextBoxUsername") as TextBox;
TextBox1.Focus();