Develop Reference

Dynamic ModalPopupExtender not firing the OK Click event

ASP.NET 4.7.2 Web Forms c# VS 2019
I am trying to use a modalpopupextender to prompt for new data for foreign key fields. Like the form itself, the MPE is built on the fly in code -- in this case the click handler for the hidden button that the Javascript fires off to build and show the MPE.
I read every single article on SO and the ASP forums and tried everything I saw there. No joy. I get the popup perfectly. Hitting OK closes the popup, but never fires the OK Event.
Here is the code:
//Building the form, we do this in OnInit:
// AJAX Update Panel
UpdatePanel PUP = new UpdatePanel()
{
ID = "PUP",
};
PlaceHolder.Controls.Add(PUP);
// HiddenField containing the field name to permit
// creating the correct modalpopup.
HiddenField HFPopupField = new HiddenField()
{
ID = "HF_POPUP"
};
PUP.ContentTemplateContainer.Controls.Add(HFPopupField);
// Create Hidden button to track the popup
Button BPopup = new Button()
{
ID = "BPOPUP",
UseSubmitBehavior = false
};
BPopup.Click += BPopup_Click;
BPopup.Attributes.Add("style", "display: none;");
PUP.ContentTemplateContainer.Controls.Add(BPopup);
// And create the background panel for the popup.
Panel PnlPopup = new Panel()
{
ID = "PNLPOPUP",
CssClass = "MpeBackground"
};
PnlPopup.Attributes.Add("style", "display: none;");
PUP.ContentTemplateContainer.Controls.Add(PnlPopup);
/// Event handler for hidden button.
protected void BPopup_Click(object sender, EventArgs e)
{
[snip -- code to get the dataset that is being filled]
UpdatePanel PUP = Placeholder.FindControlRecursive("PUP");
Table T = new Table()
{
CssClass = "PopupTbl"
};
TableRow TRTitle = new TableRow();
TableCell TCTitle = new TableCell()
{
CssClass = "PopupTitle",
ColumnSpan = 2
};
Label LPopTitle = new Label()
{
Text = [title of the popup]
};
TCTitle.Controls.Add(LPopTitle);
TRTitle.Cells.Add(TCTitle);
DataRow drData = null;
// Add Fields, and also the cancel and Add buttons
foreach (DataColumn DC in dsColumns.Tables[0].Columns)
{
TableRow TRColumn = [create a tablerow with 2 columns, a prompt and the input field]
if (TRColumn != null)
{
T.Rows.Add(TRColumn);
[snip]
}
} // end of foreach(DataColumn DC in dsColumns.Tables[0].Columns)
PnlWindow.Controls.Add(T);
TableRow TRButtons = new TableRow();
TableCell TCButtons = new TableCell()
{
ColumnSpan = 2,
CssClass="PopupButtons"
};
Button MPEBOK = new Button()
{
ID = "MPE" + sFieldName + "_MPEBOK",
Text = "OK",
CausesValidation = false,
UseSubmitBehavior = false
};
MPEBOK.Click += MPEBOK_Clicked;
TCButtons.Controls.Add(MPEBOK);
LiteralControl LCB = new LiteralControl()
{
Text = " "
};
TCButtons.Controls.Add(LCB);
//************************************************************
//*** Postback Trigger ***
//************************************************************
AsyncPostBackTrigger trigger = new AsyncPostBackTrigger()
{
ControlID = MPEBOK.ID,
EventName = "click"
};
PUP.Triggers.Add(trigger);
//************************************************************
//*** Cancel Button ***
//************************************************************
Button MPEBuhBye = new Button()
{
ID = "MPE" + sFieldName + "_BUHBYE",
Text = "Cancel",
UseSubmitBehavior = false
};
TCButtons.Controls.Add(MPEBuhBye);
TRButtons.Cells.Add(TCButtons);
T.Rows.Add(TRButtons);
PnlPopup.Controls.Add(PnlWindow);
AjaxControlToolkit.ModalPopupExtender MPE = new AjaxControlToolkit.ModalPopupExtender()
{
ID = "MPE" + sFieldName,
PopupControlID = "PNLPOPUP",
TargetControlID = "BPOPUP",
BackgroundCssClass = "MpeBackground"
};
// Add the MPE to the UpdatePanel.
PUP.ContentTemplateContainer.Controls.Add(MPE);
// Show the modal popup extender.
MPE.Show();
}
protected void MPEBOK_Clicked(object sender, EventArgs e)
{
[snip - this never fires]
}
I cannot find out what is happening here. Can anyone see something hinky?
Thanks
John.

You can't add a server side button or inject a server side button into the page DOM.
When you drag a asp.net button onto the form, BOTH the "mypage.cs" and mypage.desinger.cs ARE updated. The wire up of the button occurs at design time, and you would have to modify mypage.desinger.cs ALSO and ADD a button event stub.
So you can't do this.
A compromise would be to also add some js and have that HTML button execute a .click() method of a hidden asp.net button you drop into that page (that would give you the post back, and the running behind of a separate button event code stub.
This event resolution occurs at compile time - not at page render time. You have to drop that button onto the page.
I suppose you could adopt a standard that you always place right below that "div" on the page the button (hidden with style=none. And then as noted, have your injected code along with some js execute a click on the hidden button. Or just have the js button code execute a __doPostback("some value") and pick this up in the page on-load event, and then call the routine (function) from on-page load event.
I think better would be to use a jQuery.UI dialog, as that dialog CAN say load + use another different web page into a “div” on the existing page. So you layout, make, and create the nice looking popup form as a separate web page. jQuery is able to remove the “form” and additonal tags out of that page load, and then inject it into the existing page. (that code would be rather hard to re-produce). so jQuery.UI is able to pop up that separate page. however, the buttons on that loaded page (into that div) of course can't really run any code behind in the current page. However, the buttons CAN run local js in the current page. Thus the actions of this injected page would be local to each page. But the popup would not be directly calling a code behind stub.
Now, to adopt jQuery.UI, then you also have to of course adopt jQuery. So that is two extra libraries you need. (but, jQuery you likely already have).
However, I suppose the whole point of using the ajax toolkit is to avoid jQuery.ui in the first place. To be fair, before jQuery.ui came along, that tool kit was REALLY impressive, and gave asp.net folks a REAL leg up on the competition. (and it tends to be MUCH less wiring up then say using jQuery.UI
So the AjaxToolkit in its heyday was impressive. Now, it of course showing its age, but I still use the kit, and this is especially the case for the AjaxFileUploader. And yes I do use the popups – even to this day. However, I find now that jQuery.UI dialogs are more flexible, and would be better in this case (because you want a on-the fly setup).
Also, having code behind buttons in even the jQuery.UI dialog, or in this case the ajax popup? Well, only the action button can run code behind. The cancel button of course will just dismiss the dialog. However, any button in the dialog that WILL run code behind? Well, that's ok, since you have a page post back, and it actually the page postback that BLOWS out the dialog anyway.

Issue while enabling hyperlinks in master page from content page

I had written code to Enable and disable hyperlinks on master page from the content page. Every thing is working fine and the hyperlinks are getting disabled also after calling the DisableHyperlinkInMasterPage Method. When i am calling the EnableHyperlinkInMasterPage method still the hyperlinks are not working. If we are leaving that page , then i found that the hyperlinks starts working. My issue is after calling the EnableHyperlinkInMasterPage method , without leaving the page the hyperlinks are still disabled and not working and after leaving the page it getting enabled . Please help me that how i fix this issue.I debug the code and not found any error on EnableHyperlinkInMasterPage method.
private void DisableHyperlinkInMasterPage()
{
AssociateMaster mymaster = (AssociateMaster)Page.Master;
HyperLink home = (HyperLink)mymaster.FindControl("Home");
home.Enabled = false;
HyperLink profile = (HyperLink)mymaster.FindControl("ProfileLink");
profile.Enabled = false;
HyperLink report = (HyperLink)mymaster.FindControl("Report");
report.Enabled = false;
HyperLink signout = (HyperLink)mymaster.FindControl("SignOut");
signout.Enabled = false;
}
private void EnableHyperlinkInMasterPage()
{
AssociateMaster mymaster = (AssociateMaster)Page.Master;
HyperLink home = (HyperLink)mymaster.FindControl("Home");
home.Enabled = true;
HyperLink profile = (HyperLink)mymaster.FindControl("ProfileLink");
profile.Enabled = true;
HyperLink report = (HyperLink)mymaster.FindControl("Report");
report.Enabled = true;
HyperLink signout = (HyperLink)mymaster.FindControl("SignOut");
signout.Enabled = true;
}

Try using properties to enable and disable links. And try using FindControl as less as you can. Consider you have a link in your MasterPage named lnkTest. Write this code in your master page:
public bool TestLinkEnabled
{
get { return lnkTest.Enabled; }
set {lnkTest.Enabled = value; }
}
Then in your content page after adding this line to your page:
<%# MasterType VirtualPath="~/MasterPage.master" %>
enable and disable this link using:
Master.TestLinkEnabled = true;
Master.TestLinkEnabled = false;

Asp.net - Can't Change Visibility of Panel After Downloading File

I am displaying a panel that containg a button. When the user clicks the button, it does some processing and then downloads a file for the user. The code for that is shown here:
private void OpenForm(string content, string formName)
{
Byte[] bytes = System.Text.Encoding.Default.GetBytes(content);
this.Response.AppendHeader("Content-Type", "application/msword");
this.Response.AppendHeader("Content-Length", bytes.Length.ToString());
this.Response.AppendHeader("Content-disposition", "attachment; filename=" + formName);
this.Response.BinaryWrite(bytes);
ReturnToMemberScreen();
this.Response.Flush();
this.Context.ApplicationInstance.CompleteRequest();
}
In the function ReturnToMemberScreen, I am changing the visibility of some panels. Here is the function:
private void ReturnToMemberScreen()
{
this.panelMappings.Visible = false;
this.MemberEditPNL.Visible = true;
}
I can download the file perfectly fine, my issue is that the visibility of my panels don't change. Does it have something to do with writing to the Response like I am?

Do not use Visible = false as that causes the element to not be rendered. Try:
// To hide:
Panel1.Style.Add("display", "none");
// To show:
Panel1.Style.Add("display", "block");

Do you set the visibility of the panels in the Page_Load event? If so, and if you're not handling postbacks within the event, then the visibility settings might be overriding the settings in ReturnToMemberScreen.

Looking closer, I think I cannot make any changes to the page because I am changing the Content-Type of the response from "text/html" to application/msword when I do this:
this.Response.AppendHeader("Content-Type", "application/msword");
As I result, I am making all my changes with CSS and Javascript instead. By default, I set my panels to either show or hide using css:
.hide
{
display:none;
}
.show
{
display:block;
}
Then I set the OnClientClick of the button to the following Javascript function to change the display:
function visible()
{
document.getElementById('<%=panelForms.ClientID %>').style.display = 'none';
document.getElementById('<%=MemberEditPNL.ClientID %>').style.display = 'block';
}

Change page state with JavaScript, old state gets recalled on postback

Basically we have the "illusion" of an notification message box that exists as .Visible = false in the MasterPage. When it comes time to display a message in the box, we run a method that looks like this:
public static void DisplayNotificationMessage(MasterPage master, string message)
{
if (Master.FindControl("divmsgpanel") != null)
{
master.FindControl("divmsgpanel").Visible = true;
}
if (master.FindControl("divdimmer") != null)
{
master.FindControl("divdimmer").Visible = true;
}
TextBox thetxtbox = (TextBox)master.FindControl("txtboxmsgcontents");
if (thetxtbox != null)
{
thetxtbox.Text = message;
}
}
Basically through our designers awesome CSS voodoo, we end up with what appears to be a floating message box as the rest of the page appears dimmed out. This message box has a "Close" button to dismiss the "popup" and restore the dimmer, returning the site to the "normal" visual state. We accomplish this with JavaScript in the MasterPage:
function HideMessage() {
document.getElementById("<%# divmsgpanel.ClientID %>").style.display = 'none';
document.getElementById("<%# divdimmer.ClientID %>").style.display = 'none';
return false;
}
and the button's declaration in the .aspx page calls this HideMessage() function OnClientClick:
<asp:Button ID="btnmsgcloser" runat="server" Text="Close" style="margin: 5px;"
OnClientClick="return HideMessage()" />
The problem:
All future postbacks cause the MasterPage to "remember" the state of those divs from how they were before the HideMessage() JavaScript was executed. So in other words, every single postback after the initial call of the DisplayNotificationMessage() method causes the page to return to divmsgpanel.Visible = true and divdimmer.Visible = true, creating an endlessly annoying message box that incorrectly pops up on every postback.
The question:
Since we want the Close function to stay client-side JavaScript, how can we "notify" the page to stop reverting to the old state on postback, for just these two divs?

Can you try setting them to Visible = false in Master_Page Load event? It should hide them and reshow them just when you call DisplayNotificationMessage

How to initialize textbox to hide for first display and still have jquery work

So I now have the following jquery to hide or show a textbox based on specific values selected in a DropDownList. This works except that I need the first display of the popup to always be hidden. Since no index change was made in the drop down list, the following does not work for that. If I code it as visible="false", then it always stays hidden. How can I resolve this?
<script language="javascript" type="text/javascript">
var _CASE_RESERVE_ACTION = "317";
var _LEGAL_RESERVE_ACTION = "318";
function pageLoad() {
$(".statusActionDDLCssClass").change(function() {
var value = $(this).val();
if (value == _CASE_RESERVE_ACTION || value == _LEGAL_RESERVE_ACTION) {
$(".statusActionAmountCssClass").attr("disabled", false);
$(".statusActionAmountCssClass").show();
}
else {
$(".statusActionAmountCssClass").attr("disabled", true);
$(".statusActionAmountCssClass").hide();
}
});
}
</script>
Thank you,
Jim in Suwanee, GA

If you set
visible=false
.Net will not render it. You can do
style="display:none;"
and .Net will render the tag properly but CSS will hide it from the user.

Add the following to pageLoad function
function pageLoad(sender, args) {
$("input.statusActionAmountCssClass").hide();
.... rest of code .....
}
By the way, I would recommend using the selector $("input.statusActionAmountCssClass") to get a jQuery object containing a reference to your input, otherwise jQuery will search all elements to match the CSS class .statusActionAmountCssClass
EDIT:
Another change that could also be made is to use jQuery's data() to store the two global variables
$.data(window, "_CASE_RESERVE_ACTION","317");
$.data(window, "_LEGAL_RESERVE_ACTION","318");
then when you need them simply cache the value in a local variable inside the function
function someFunctionThatNeedsGlobalVariableValues() {
var caseReserveAction = $.data(window, "_CASE_RESERVE_ACTION");
var legalReserveAction = $.data(window, "_LEGAL_RESERVE_ACTION");
}
this way, the global namespace is not polluted. See this answer for more on data() command