I have a requirement where I ask user for confirmation and also display messages.
The programmers used for this were from Windows forms background. Hence have used the MsgBox in every nook and corner. Even in business logic part they have used the Messageboxes which requires Yes/No style confirmation from user.
When we tested the site from the remote machine we found that it gives error of using DefaultDesktopOnly/ServiceNotification. But when tested we found that this is totally different from what we were looking for.
Now my requirement is a confirmation box is shown from the code like Delete record" yes no and based on the reply we take the action.
This is to be done using updatepanel.
As you use this code in several places, I suggest you make a custom control, that takes your message and displays and Update panel with message and yes/no buttons.
Internally set some value for yes, no, cancel... so that you get something just like MessageBox.
Update panel or not, you'll have to attach some javascript that would call confirm() javascript function. Based on it's result you cancel javascript default link/button behaviour...
This will give you something to scratch your head for a start:
http://www.dotnetfunda.com/tutorials/ajax/updatepanel.aspx
That's not really a question, but a requirement.
Anyway ... MessageBox is a Windows function, it is not an HTML or browser function. Now you can mimic it in one of two ways, via a javascript confirm function or via Yes/No buttons and the appropriate event.
Given that your requirements are for something that works in an update panel I'd guess that wiring up javascript events manually for this isn't going to be something you are comfortable with, so I'd suggest an asp:Panel inside the UpdatePanel which has yes and no buttons, with server side events bound to them. In the UpdatePanel logic show this when you want confirmation and hide everything else, the act accordingly.
If you want to do server-side confirms, you'll get into more complicated code generation. First of all, you'll have two views. The first one has a link/button delete but will actually be just a postback to the second view that will display confirmation form with yes/no. In this form, your yes button will actually be your delete action...
But I'd still chose a hybrid (especially if this is a grid we're talking about) of javascript and serverside (since alert() and confirm() are evil from user experience perspective):
you have a linkbutton delete
when user clicks on it, you replace this control with a div, that displays two linkbuttons yes/no
send a postback with one of the two
Addendum
No linkbutton could be just dummy, to hide this confirmation and display delete again - so it means there won't be any server round trip
you could even create a usercontrol that mimics this sophisticated delete link behaviour to make it reusable application wide.
Related
Such a button is not rendered to the browser, so is there any way a malicious user would be able to trigger the action defined by the invisible button? e.g. with a JavaScript call to WebForm_DoPostBackWithOptions? Would ASP.NET accept a POST that appeared to be triggered by this button, even though it wasn't rendered?
Short answer yes.
It is always up to you (the developer) to ensure data received from user input (in this case a post) is valid. Having said that the asp.net framework will do a lot of verification for you, such as "suspicious looking post values".
It is possible to construct a post to a web endpoint, even if the page you display does not have a submit button.
Edit
This would be an example of security through obscurity and is generally not a best practice. Asp.Net "submit" buttons modify a hidden form field called __EVENTTARGET. The asp.net handlers will inspect this field when determining a button click "event". This value can be spoofed if the attacker knew the name of the event target.
Hiding/showing UI elements are good for improving the user experience, but you should always validate (on the server) user input before performing any business actions.
I don't believe it would, if it's not rendered it shouldn't accept the postback. .net uses hidden fields on the page to know which controls were on the page and can verify that during postback, so it knows what triggered the post back. if the control was not there to begin with it shouldn't accept it.
Yes, this is definitely possible. ASP.NET accepts all POST values for controls defined on the page, visible or not. Beware too of i.e. textfields that are set to "read-only". Don't use readonlyControl.Text after the post, and trust that it has the same value as it had the last time you set it.
Take a look at what is posted when you perform a submit with ASP.NET with i.e. Chrome Developer tools, Fiddler, etc, and you should be able to figure out how to add your own value to an "invisible" text field.
hello friends i have a check box list which contains all the courses kept in the data base(on page load) now i want that on some event of check box list all branches corresponding to each checked box of course check box list should be list in another check box list(that is the business logic i will do my own) but the problem is that i am not finding any event where i can send all selected check box list value and can generate appropriate result, if any alternate control or solution you can suggest then please suggest me this.
Set the AutoPostBack property to true and in the SelectedIndexChanged event you can loop over the elements that are selected and then bind your second control depending on that.
Another option would be to go for an ajax solution. For this I suggest you take a look at the change event in jQuery to bind to your checkboxlist and use the ajax stack to retrieve the extra information as html and plug that into a span as innerHtml.
I think you need to clarify where your logic sits, and where the information required for that logic to work sits - in order to even know whether you're dealing with a client-side or a server-side technology question
There's two basic possibilities:
Either all required inforamtion is already in the loaded page. In that case, this is basically a javascript problem. I'd dive a bit into jQuery here which has excellent capabilities of finding elements based on properties, and manipulating them
Alternatively, some of your logic and/or data remains on the server. In that case, you can
go with the AutoPostBack property XIII mentioned, resulting, as you correctly assume, in a reload after every click.
Have the user click all the checkboxes they like, and then have them click on a "do something now" button which performs a single postback
Transmit the information about the checkbox click to the server via javascript, get a response, and select other boxes accordingly. Again, XIII already mentioned that by "ajax solution".
So I'm just trying to elaborate on what different approaches do for you, and what questions you need to answer yourself before you can proceed to a concrete technical solution.
I am a little confused and making it alot more complicated than this needs to be! Here is what I have...
A view which displays a drop down of US States. When the user chooses a state it loads a list of data from a database and returns the results (populates the View Model) and the View renders the information.
What I wanted to do was have have the dropdown trigger an Ajax event which performs the data load, but also wanted it to depreciate if the user didn't have Javascript enabled. How would I go about rendering the view with AND without javascript / ajax?
Hope that makes sense. Thanks for your help.
You can't re-populate a drop-down without jscript. You can do a page-reload with a new drop-down though, although the logic to determine which to use is javascript unfortunately. (Not to mention triggering the re-load of the page on click)
No Javascript support though? That seems kind of out of date, most people run javascript-enabled browsers these days. As for paranoia freaks with javascript turned off, a <noscript> block to tell them to get over it may be appropriate.
To do this with ajax, read this article about cascade dropdowns by Stephen Walther.
To do this without ajax, you could put your first dropdown in a form with a button visible only when javascript is disabled (hide this with javascript for that) wich gets to some action (in another window, maybe) wich returns the second dropdown populated according to the element selected on the first (on the first window, if you have 2 - you could know this url using a viewstate variable).
I have a User control (because I use the same in other page, so I thought I should reuse code and not double my work), but in this page I show a list of companies and each one has a company number, I need to pass this company number to that User Control and it has to reload using that passed company number.
How can I accomplish this?
what I have so far:
alt text http://www.balexandre.com/temp/2009-09-17_0917.png
the Show company structure link is made of
<a href="javascript:showStruct('112:201334607','5564967221');"
class="showStructLink">Show company structure</a>
the showStruct method is written like
function showStruct(pid, cnr) {
if (_showStrut == 0)
return;
// fancy stuff to be more apealing visually
$("#tdSearch").removeClass("tabTitleUp01").addClass("tabTitleDownUp01");
$("#tdStruct").removeClass("tabTitleDownUp02").addClass("tabTitleUp02");
$("#srtr1").hide();
$("#srtr2").hide();
$("#sttr1").show();
// enable Search Results tab to be clicked in order to get back
$("#tdSearch")
.addClass("pointer")
.bind("click", function() { hideStructure(); });
// pass the company number and reload wcCompanyStruture web user control
// __doPostBack('RefreshWebUserControl', cnr);
}
I can make a simple aspx page with the control inside and from jQuery invoke $.get() to run and populate the control correctly, but I really want to learn how to do this properly, using the ASP.NET AJAX Method to send a number and call RefreshData on it
using code-behind it is easy to refresh the user control, just invoking
wcCompanyStruture.RefreshData("companyNumberHere");
what do I need to do in my User Control side and well in the showStruct method to create this behavior?
All help is appreciated, Thank you.
I know this is not the answer to you question but I think you may be asking the wrong question.
It looks to me as if you have a search result+details view scenario that you are going about the wrong way.
When you click "Show Company structure" you want to see the details on the second tab right? If this is the case then the tab approach would be confusing to the user, it would be better with a modal popup that shows the details. No postback just AJAX load a page with the details into a modal popup window.
This is very easy with JQuery using the dialog widget in JQueryUI and the AJAX load function $('#SomeDiv').load('details.aspx?id='+companyid);
http://docs.jquery.com/Ajax/load#urldatacallback
It would give a much better user experience and it is surprisingly simple to code.
I hope this helps.
You can use a LinkButton for each "Show Company Structure" link, and set the CommandArgument property with the corresponding company id. The LinkButton will cause a postback.
A second solution would be to use a hidden variable : <input type="hidden" id="hiddenCompanyNumber"> and set it's value in the showStruct method. You can then call __doPostBack(), for which you need a control upon which to postback I think.
All in all, I think the first solution is less hacky.
You can find it here
http://codeclimber.net.nz/archive/2007/06/26/how-to-refresh-an-updatepanel-from-javascript.aspx
don't worry about the article title it has what you need Just do the four steps and you are ready to go.
I'm writing an asp.net web app. and i've hit a bit of a brick wall.
basically i have 2 pages, the main page with a text box in and a popup that contains a treeview.
My problem is this. when i select a treeview item i want the program to perform some database transactions using asp.net and then pass the value retrieved from the database into a javascript function that passes the data back from the popup page to the parent page. My problem is that i cannot find any way of calling a javascript function from asp.net. I've tried assigning attributes to controls on page load, but this does not work as when the page loads the data has not been retrieved from the database.
Have a look at the ClientScriptManager class. You can register scripts from code-behind that will run when the HTML page loads. Those scripts can call other javascript functions on the page.
There are many tutorials and examples on the Web. Here's one I found that may help but there are many more.
How to use the client script manager
You hit the nail on the head when you said "I've tried assigning attributes to controls on page load, but this does not work as when the page loads the data has not been retrieved from the database." You just need to discover when you're pulling the data from the database, and then assign the values after that. Without looking at your code, there's no way to know for sure, but Page_PreRender is probably a good bet to assign your values...it's probably after you're pulling information from the db...it's pretty much the last place that you can make things happen before the html is generated for the client.
You can invoke a function resided in the Main Page and call that function in the Main Page from the Child Page which is your pop up window.
Please refer to these links for references
http://chiragrdarji.wordpress.com/2007/03/10/call-parent-windows-javascript-function-from-child-window-or-passing-data-from-child-window-to-parent-window-in-javascript/
http://www.webmasterworld.com/forum91/2957.htm
http://hspinfo.wordpress.com/2008/01/12/call-parent-windows-javascript-function-from-child-window/
This one helps with retrieving popups from values using javascript
http://www.eggheadcafe.com/articles/20060117.asp
This one shows how to fire a postback using javascript, and manage it in the codebehind.
http://weblogs.asp.net/mnolton/archive/2003/06/04/8260.aspx
If you put them together, and use Control.ClientID to find the actual "html name" of your asp.net controls, you'll be able to set that up in no time.
Might not be the prettiest way to do it in town, and incidentally make little baby Jesus cry, but anyway, it works.
[edit]Oh. I just saw that it seems I answered the question the other way around, or "how to trigger codebehind from Javascript". I think the method I suggest may help you, if you use it right.
The javascript of the popup should pass the information to the parent window, and the parent window function should call a postback when it receives the information.
The javascript of the popup window should be only registered on a postback with the correct information retrieved, so that when the postback occurs on the popup because of the selection of the right information, the window closes and passes the information to the parent page.
The parent page, triggering postback, does the thingies you need it to, and the app resumes "normally" from there on, doing whatever you need it to, outside of the popup page.