on every postback page opens in a new tab - asp.net

I have a weird problem in my page. I have a button called Print. I wanted report should come in a new tab, so i wrote some javascript on button's onClientClick. Which works great with no problem at all.
But problem starts now when user comes back on original page again, now here i have several controls which cause postback. Say for example its a dropdownlist. so whenever user changes dropdown item it causes postback which is fine but everytime it opens a new tab on every postback.
hope I am clear in question...
Any help??
Here is a code:
<asp:Button ID="btnshow" runat="server" Text="Show" Font-Bold="true" ForeColor="Black" Width="90px" OnClick="btnshow_Click" OnClientClick ="document.forms[0].target = '_blank';"/>

The issue is document.forms[0].target='_blank' is setting the target on the form not the individual button so a postback triggered by any control will open in a new tab.
You should use a HyperLink control instead of the Button control. The HyperLink control has a Target property which allows you to specify how the link should be opened.
Below is an example taken from the HyperLink documentation. This will render an anchor tag with target="_blank".
<asp:HyperLink ID="lnkPrint" NavigateUrl="http://www.microsoft.com" Text="Print" Target="_blank" runat="server" />

Related

Asp.net Button Firing Other Button's Event

I have a set of options on an ASP.net page where the user may open up one of two lightboxes - either the "Add" lightbox or the "Edit" lightbox.
Each one has a small form for the user to fill out, and then they can hit a button at the bottom of the lightbox to hit submit.
I have the buttons set up within the lightboxes like so:
<asp:Button Id="btnSubmitAdd" runat="server" Text="Submit" OnClick="btnSubmitAdd_Click" />
... then later in the other lightbox...
<asp:Button Id="btnSubmitEdit" runat="server" Text="Submit" OnClick="btnSubmitEdit_Click" />
When i click the "Add" lightbox's submit button, everything behaves just fine.
When i click the "Edit" lightbox's submit button however, it fires "btnSubmitAdd_Click" instead of its own "...Edit_Click" event!
I have checked and re-checked all of the names and events and everything is set up correctly. Anyone have any ideas why this is happening?
Thanks to #MikeGuthrie for leading me down the correct path!
The issue seems to be with asp.net defaulting buttons to type "submit" which submits the entire form, and apparently that means it simply hit the first button's event before the second.
I added have modified the buttons like so and things are working now:
<asp:Button Id="btnSubmitAdd" runat="server" Text="Submit" OnClick="btnSubmitAdd_Click" UseSubmitBehavior="false"/>
<asp:Button Id="btnSubmitEdit" runat="server" Text="Submit" OnClick="btnSubmitEdit_Click" UseSubmitBehavior="false"/>

OnTextChanged loses focus when AutoPostBack is true

I have a ASP.Net webform that has several textboxes. Some of the textboxes have an OnTextChanged event with AutoPostBack set to true.
When the user enters some text and leaves the textbox, I want some code to run. This part works fine.
The problem is that if a user enters some text, then clicks or tabs to another textbox, the OnTextChanged of the current textbox event fires fine but the textbox that the user clicked on does not keep focus. This causes problems because the user thinks they are on the next textbox but they aren't. And no object seems to have the focus.
Is there anything that can be done to make the next object keep focus while the OnTextChanged event of the current textbox fires?
One option is to use <asp:UpdatePanel> Control.
Facts about using it:
The postback request would be made via AJAX.
It would not recreate the whole page HTML.
When the UpdatePanel updates, it replaces the DIV innerHTML, that would make the textbox lose focus (bad point).
To maintain the focus, you would have to avoid the UpdatePanel from updating when the textbox posts back.
You can avoid the update by setting the UpdateMode and ChildrenAsTriggers properties.
Here is an example:
<asp:UpdatePanel ID="uppTextboxes" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="false">
<ContentTemplate>
<asp:TextBox ID="txb1" runat="server" AutoPostBack="true" OnTextChanged="txb1_OnTextChanged" />
<asp:TextBox ID="txb2" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Since the whole page is recreated on postback on serverside and the browser will recreate all html on clientside, you have to tell ASP.NET that your TextBox needs focus.
Use Page.SetFocus:
Page.SetFocus(IdOfControl);
However, i would prefer not to postback at all if i can. Can't you use a button that the user has to click after he has entered all necessary data?

ASP.NET Textbox: OnTextChange jumps to top of page because of autopostback

I'm using the OnTextChange event on a textbox on an ASP.NET page. To have this working I have to put 'AutoPostBack=true'.
The problem is that the textbox is on the bottom of the page, and when the text changes it has to fill another textbox. This is working fine but when the event triggers the page refreshes and jumps to the top of the page, so I always have to scroll down again to see it. (Due to the autopostback)
Is there anything I can do to prevent it to jump to the top of the page?
Use UpdatePanel and put that text box for which u r triggering OnTextChange event in of from ajax extensions and dont forget to include scriptmanager at top of the page
the code goes like this
<asp:UpdatePanel>
<content>
<asp:TextBox runat="server" AutoPostBack="true" OnTextChanged="textbox_textchanged">
</asp:TextBox>
</content>
</asp:UpdatePanel>
In the page_load event write below code.
this.MaintainScrollPositionOnPostBack = true;

link button property to open in new tab?

In my application I have some link buttons there but when I right click on them I cannot (they are in disable mode) find the menu items Open in new tab or Open in new window.
How do I show those menu items?
Code example:
<asp:LinkButton id="lbnkVidTtile1" runat="Server" CssClass="bodytext" Text='<%#Eval("newvideotitle") %>' />
From the docs:
Use the LinkButton control to create a hyperlink-style button on the Web page. The LinkButton control has the same appearance as a HyperLink control, but has the same functionality as a Button control. If you want to link to another Web page when the control is clicked, consider using the HyperLink control.
As this isn't actually performing a link in the standard sense, there's no Target property on the control (the HyperLink control does have a Target) - it's attempting to perform a PostBack to the server from a text link.
Depending on what you are trying to do you could either:
Use a HyperLink control, and set the Target property
Provide a method to the OnClientClick property that opens a new window to the correct place.
In your code that handles the PostBack add some JavaScript to fire on PageLoad that will open a new window correct place.
Here is your Tag.
<asp:LinkButton ID="LinkButton1" runat="server">Open Test Page</asp:LinkButton>
Here is your code on the code behind.
LinkButton1.Attributes.Add("href","../Test.aspx")
LinkButton1.Attributes.Add("target","_blank")
Hope this will be helpful for someone.
Edit
To do the same with a link button inside a template field, use the following code.
Use GridView_RowDataBound event to find Link button.
Dim LB as LinkButton = e.Row.FindControl("LinkButton1")
LB.Attributes.Add("href","../Test.aspx")
LB.Attributes.Add("target","_blank")
try by Adding following onClientClick event.
OnClientClick="aspnetForm.target ='_blank';"
so on click it will call Javascript function an will open respective link in News tab.
<asp:LinkButton id="lbnkVidTtile1" OnClientClick="aspnetForm.target ='_blank';" runat="Server" CssClass="bodytext" Text='<%# Eval("newvideotitle") %>' />
This is not perfect, but it works.
<asp:LinkButton id="lbnkVidTtile1" runat="Server"
CssClass="bodytext" Text='<%# Eval("newvideotitle") %>'
OnClientClick="return PostToNewWindow();" />
<script type="text/javascript">
function PostToNewWindow()
{
originalTarget = document.forms[0].target;
document.forms[0].target='_blank';
window.setTimeout("document.forms[0].target=originalTarget;",300);
return true;
}
</script>
LinkButton executes HTTP POST operation, you cant change post target here.
Not all the browsers support posting form to a new target window.
In order to have it post, you have to change target of your "FORM".
You can use some javascript workaround to change your POST target, by changing form's target attribute, but browser will give a warning to user (IE Does), that this page is trying to post data on a new window, do you want to continue etc.
Try to find out ID of your form element in generated aspx, and you can change target like...
getElementByID('theForm').target = '_blank' or 'myNewWindow'
When the LinkButton Enabled property is false it just renders a standard hyperlink. When you right click any disabled hyperlink you don't get the option to open in anything.
try
lbnkVidTtile1.Enabled = true;
I'm sorry if I misunderstood. Could I just make sure that you understand the purpose of a LinkButton? It is to give the appearance of a HyperLink but the behaviour of a Button. This means that it will have an anchor tag, but there is JavaScript wired up that performs a PostBack to the page. If you want to link to another page then it is recommended here
that you use a standard HyperLink control.
It throws error.
Microsoft JScript runtime error: 'aspnetForm' is undefined
<asp:LinkButton ID="LinkButton1" runat="server" target="_blank">LinkButton</asp:LinkButton>
Use target="_blank" because It creates anchor markup. the following HTML is generated for above code
<a id="ctl00_ContentPlaceHolder1_LinkButton1" target="_blank" href="javascript:__doPostBack('ctl00$ContentPlaceHolder1$LinkButton1','')">LinkButton</a>

Trying to self contain pop ups which use the AjaxToolkit ModalPopUpExtender

I have 3 different kinds of ajax popups that need to exist across my site. I was hoping that I could simply create a user control for each one and place the panel and modal popup extender inside each one but this doesn't seem to be working. Has anyone tried this before or do you have a recommendation as to how I can avoid duplicate code for each pop up on different pages? Thanks!
Ah I figured out my issue with the User Control I believe.
The ModalPopUpExtender requires the TargetID property to be set otherwise an error occurs. Since this is sitting in a UserControl I just created a dummy link button that doesn't do anything and I set the property visible to false.
<asp:LinkButton ID="lnkBlank" runat="server" Visible="false" />
<asp:Panel ID="plContainer" style="display: none;" runat="server">
Hello?
</asp:Panel>
<cc1:ModalPopupExtender ID="mpe" runat="server"
BehaviorID="test"
TargetControlID="lnkBlank"
PopupControlID="plContainer" />
Apparently it doesn't appreciate that and the moment I set the visible property to true it started working. Not sure what the reasoning is for a TargetID since, I would think, most pop ups could be called from multiple links about the page. Perhaps I'm still not entirely clear on how this control is supposed to be used.
One option would be to write the popups in a asp.net user control (a .ascx page) and include that on the pages you need the popups. Have a public method in the ascx page that will show the popup, and call it from the parent page when you need to. If you already have a script manager on the parent page, you can't have a second one in the ascx page, but other then that there shouldn't be anything that would stop this from working. Hope this helps!
edit: here's what my modal popup extender control looks like...
<cc1:ModalPopupExtender
ID="mpeClassroom"
BackgroundCssCLass="modalBackground"
runat="server"
CancelControlID="lbClose"
OnOkScript="onOk()"
TargetControlID="Button1"
PopupControlID="pnlClassroom">
</cc1:ModalPopupExtender>
in my code behind page, my method just calls mpeClassroom.Show();
The problem with hidden link as TrgetControlID is that; when u set its visibility as false, server doesn't render it as well. PopExtender then cannot find control on the page.
Instead of setting its visibility to false, try to apply a style with display:none. This should work !

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