I'm having a difficult time getting around AutoPostBack with ASP.NET components, and was hoping someone can help. I've looked through multiple queries but nothing is really helping.
I have a 'Submit' button on my page that when clicked should do 2 things:
1. Run a server-side C# function that updates a bunch of <asp:Labels in a div tag.
2. Run a javascript animation that moves stuff around and makes the <div tag visible.
My functions work just fine by themselves, however my issue is with autopostback. If I use an <asp:Button the postback refreshes and the javascript animation is undone along with it. If I use an <input type="button" tag I am unable to run both the C# and Javascript functions. I've tried the following:
<input type="button" runat="server" onclick="c#function" onclientclick="javascriptFunction(); return false;"
** runat="server" seems to just enable postback on that button
<asp:Button
** C# function uses Page.ClientScript.RegisterStartupScript to invoke javascript function, but postback defeats the animation.
I'm hoping to keep the javascript animations as they make the interface very clean and intuitive, so any help in keeping it is greatly appreciated. Any suggestions?
You may use ajax. You can pass values to the server page thru ajax and let the server page handles (insert a record in table / send an email to someone / whatever....) it for you and return a result to you. Till you get your result. you can show a "Processing..." Message to the user.
Here is a plugin to have the block effect.
http://jquery.malsup.com/block/
The below is a small example of how to do it in ajax (with jquery)
HTML
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.2/jquery.min.js"></script>
<head>
<body>
<input type="button" id="btnGetProd" value="Get Products" />
<div id="divProducts"></div>
<script type="text/javascript">
$("#btnGetProd").click(function(){
$("#divProducts").html("Processing your request....</div>").fadeIn(100, function ()
{
$.ajax({
url: "myajaxserverpage.aspx?mode=getprodcusts&category=3",
success: function (data) {
$("#divProducts").html(data).fadeIn(100);
},
error: function (req, textStatus, error) {
alert("Some error occured");
}
})
});
});
</script>
</body>
</html>
and you should have a page called myajaxserverpage.aspx which returns the content (ex: A list of products) for the div called "divProducts"
What the above code does is , When the user click on the button, it shows the text "Processing your request..." in the div and then make an ajax call to the aspx page.Once it receives the response, it put that to the div and then do a fadeIn effect.
what you are experiencing is expected. the browser will execute the javascript and then send a request to the server. the server processes the request and send a response. the client will then render the response. At this point any UI changes you made are discarded because a new request was received.
To get around this you will need to incorporate ajax into your page.
alternative way to reach your needs
1.let button do only javascript function
2.let javascript function do the postback after u finish your animation
ajax is not requirement
Related
I'm using an Asp.net/C# environment and Visual Studio 2013 to create a web application.
I have a page (aspx) with only a single iframe in it, and a javascript method that uses jquery to put html into that frame.
<asp:Content runat="server" ID="MainSectionContent" ContentPlaceHolderID="MainSectionContentPlaceHolder">
<section runat="server" id="FrameSection" clientidmode="Static">
<asp:ContentPlaceHolder runat="server" ID="FrameSectionContentPlaceHolder" />
<iframe id="FrameContentFrame" name="FrameContentFrame" src="about:blank" seamless="seamless" onload=" loadFrameContent(); "></iframe>
</section>
<script type="text/javascript">
//<![CDATA[
function loadFrameContent() {
jQuery('#FrameContentFrame').contents().find('html').html('<%= FrameContent %>'); //FrameContent is a c# property which holds a syntactically correct html string
}
//]]>
</script>
</asp:Content>
In my code behind I fetch a long string from a server and store it in the property FrameContent. This long strings is syntactically correct html.
The result should be:
onload, the javascript method runs. The iframe is populated with html and thus the html string is shown to the user.
but what really happens:
nothing is shown. a Javascript error occurs saying "the function loadFrameContent is undefined". But its clearly there if I view the page source in my web browser. If I right click on the blank page where the frame should be, and choose "reload frame" (Google Chrome), the frame does show the Html.
So: the Html string is correct. the frame is correct. the frame can display the html correctly. However, the frame cannot display the Html onload, it needs an additional manual reload to actually show anything! I checked the page source on my browser and the Javascript function IS present, and the FrameContent property is populated with the correct html string.
As I see it, it looks like a timing issue. A blank iframe will be finished loading before your parent page, so it will call loadFrameContent before the parent page has finished parsing its dom (thus the method won't be registered). Get rid of the iframe onload and add this:
<script type="text/javascript">
//<![CDATA[
function loadFrameContent() {
jQuery('#FrameContentFrame').contents().find('html').html('<%= FrameContent %>'); //FrameContent is a c# property which holds a syntactically correct html string
}
$(loadFrameContent);
// Or if you're using an older version of jQuery
//$(document).ready(loadFrameContent);
//]]>
</script>
So.. The issue I have came across is I am migrating a client's web app to MVC2, and the original method for displaying html content is not capable of working with MVC so I am needing to update it. The functionality I need is like so: There is a side nav that will contain the actions, and say the user clicks on "FooBar" it will populate the "mainContent" placeholder with the "FooBar.html" file from a document directory. I would like to do this with no postbacks as well if it is possible. Any ideas?
You may use jQuery ajax to load the pages when user clicks on the link. load() function will be ideal here.
It is just HTML and javascript. Nothing specific to ASP.NET MVC
//Include jQuery library
<div>
<a href="Home/about" class="aLink" >About</a>
<a href="Home/FAQ" class="aLink" >FAQ</a>
<a href="Home/Contact" class="aLink" >Contact</a>
</div>
<div id="mainContent">
</div>
<script type="text/javascript">
$(function(){
$("a.aLink").click(function(e){
e.preventDefault(); // prevent the default navigation behaviour
$("#mainContent").load($(this).attr("href"));
});
});
</script>
When I load an aspx page to a popwindow using jQuery model using below code.
function OpenExceptions() {
$('#Equipmentdialog').load('Popups/Test1.aspx', function () {
$(this).dialog({
modal: true,
width: 900,
height: 400
});
});
}
I am unable to call any server side method(C# button click) in the Test1.Aspx method, When I call the the server side events, I am getting resource not found exception?
Can someone please explain me what is the reason?
Thanks
Update: this is the error I am getting
I looked at your sample project and the issue you are experiencing is very simple to explain but I am afraid it's not going to be so simple to make it work.
First I'll explain what's causing the exception.
When the dialog loads, it sets its content to whatever output is generated by the Test.aspx page. Since the page generates this HTML when you navigate to it:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><title>
</title></head>
<body>
<form name="form1" method="post" action="Test.aspx" id="form1">
<div>
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwUKMTI2NTY4ODI3MWRkmRTYlsUe3rVbAI2jDoNeA5EPuo8=" />
</div>
<div>
<input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="/wEWAgKd2MeEBAKM54rGBl+Fr2fdw6uP6072WYTIw/gz9N5E" />
</div>
<div>
<span id="Label1">Label</span>
<br />
<br />
<input type="submit" name="Button1" value="Button" id="Button1" />
</div>
</form>
</body>
</html>
The dialog ends up displaying a form whose action is set to Test.aspx; therefore, when you click on the Button on the dialog, it attempts to post back the form to Test.aspx but it doesn't find it because this page is inside Popups/Test.aspx. Now, in order to "fix it" (I say this in quotes because it's not really going to fix anything), you could change the dialog's HTML by brute force; doing something like this:
function OpenExceptions() {
$('#Equipmentdialog').load('Popups/Test.aspx #form1', function (response, status, xhr) {
response = response.replace('action="Test.aspx"', 'action="Popups/Test.aspx"'); //Make sure the form's action is accurate
$(this).html(response);
$(this).dialog({
modal: true,
width: 900,
height: 400
});
});
}
And now, when you click the Button you will no longer receive a Resource Not Found Exception; however, because this causes a normal post back the dialog will disappear, the button will post back the page and the label you have on the page will display the current date and time.
Again, this all happens because you are doing normal post backs as opposed to Ajax requests. My approach above would work if the Button in the Test.aspx page performs an Ajax request but not the kind you get when you use Update Panels and Script Managers. You won't be able to use those tools because of the way they work internally...
If you are looking to use Ajax in your app, I recommend you look at WCF Web Services in conjunction with JQuery. There are many good tutorials online on the topic.
I hope my answer at least helps you understand why this isn't working for you and why it won't work if you continue to use this approach. There are many hacks that you could apply to make it work, but I can't think of a single one that's going to be easy to maintain and scale going forward. The best approach is to do Ajax properly, using WCF web services (or Page Methods) and JQuery.
using Visual.Web.Developer.2010.Express;
using SQL.Server.Management.Studios.R2.Express;
What I'm trying to do, is get a button to run some C# when a button is clicked.. Sounds simple, right?.. I'm stuck at this part.
I have a span (Jquery UI button) being created when the user keypress's in an HTML input. As soon as they click the span, it saves what the user inputed and sends it to the database... Well, not quite yet. I'm building this and I'm stuck at this part.
One would attach the button click via attribute in the span tag, correct?
<span class="ui-state-default ui-corner-all ui-icon-disk ui-icon saveButton" title="Save" style="float:left" onclick="Button1_Click"></span>
C#
protected void Button1_Click(object sender, EventArgs e)
{
Console.WriteLine("Hello World");
}
Looks pretty simple, right? When I run this in debug, Firebug reads "Button1_Click is not defined"
...
Give me some insight here please!
My HTML/Javascript code
<script type="text/javascript">
$(document).ready(function () {
$('.hexen').after('<span class="ui-state-default ui-corner-all ui-icon-disk ui-icon saveButton" title="Save" style="float:left" onclick="Button1_Click"></span>')// ui icon
.keypress(function () {
$(this).next('.saveButton').show();
}); //adds ui icon
$('.ui-state-default').hover(
function () {
$(this).addClass('ui-state-hover');
}, function () {
$(this).removeClass('ui-state-hover');
}); //ui icon hover
$('.saveButton').click(function () {
var id = $(this).prev().attr('id'); //used in the "data" attribute of the ajax call
var value = $(this).prev().val(); //used in the "data" attribute of the ajax call
$.ajax({
type: "POST",
url: "Default.aspx",
data: "{Id: " + id + ", Value: " + value + "}",
dataType: "json",
contentType: "application/json; charset=utf-8",
success: function (data) {
console.log(data);
}
});
$(this).hide();
}); //runs ajax call and removes ui-icon after .saveButton is clicked
}); //end .ready
</script>
<input type="text" class="hexen" id="investigate1"/><br />
<input type="text" class="hexen" id="investigate2"/><br />
<input type="text" class="hexen" id="investigate3"/><br />
<input type="text" class="hexen" id="investigate4"/><br />
<input type="text" class="hexen" id="investigate5"/>
Thanks in advance!
Button1_Click is a server side button click handler which you cannot call it from client side using onclick attribute.
onclick will always look for handler or method on the client side JavaScript code.
You have to use Asp.Net button control which will render the necessary method on the page to perform postback to the server.
Once you click on Asp.Net button it will submit the current page to the server with necessary details to asp.net framework so that it will execute the required button click handler.
E.g. You can use LinkButton control like this and specify OnClick property to Button1_Click and OnClientClick property to call any client side javascript method.
<asp:LinkButton Text="Click me!"
OnClick="Button1_Click" runat="server"
OnClientClick="clientSideJavaScriptFunction()" />
From the look of it you don't need the 'onclick' handler for the span since you're binding to it in the javascript anyway:
$('.saveButton').click(....);
Also the onclick handler that you've got on the space is referencing a server side handler for C# events, not a client side handler for javascript events. The value of onclick must be a function available to the client side code in javascript. If you want to post data to the server on a button click then you need to do an AJAX request (like you are) in the javascript.
Finally the event handler you've trying to bind to .saveButton in the javascript won't work as you're trying to bind it (probably) before the document has finished loading. Move the event binding into the document.ready block after you've called after on .hexen.
I'm not sure exactly how it works in C#, but I think you need to reference the function in the URL of the ajax call.
url: "Default.aspx/Button1_Click",
Button1_Click may have to be a public function for this to work.
EDIT: Check out the "Calling the page method with jQuery instead" section of this page: http://encosia.com/using-jquery-to-directly-call-aspnet-ajax-page-methods/
I am trying to use ReCaptcha from Microsoft.Web.Helpers. If I load the entire page it renders correctly, but if I load the page with an ajax request it disappears.
Example (/home/index)
<div id="bla">
#Ajax.ActionLink("reload with ajax", "index", new AjaxOptions() { UpdateTargetId = "bla" })
#ReCaptcha.GetHtml(publicKey: "xxx")
</div>
If I enter /home/index the captcha appears. If I click the button reload with ajax the ReCaptcha disappears...
The page is loaded for the first time
reload with ajax was clicked, the contents of the page change to /home/index, in other words, the entire page reloaded asynchronous and the captcha is gone
Is there a way to fix this or a decent captcha helper for MVC 3?
I've replaced the helper with javascript. ReCaptcha script
<div id="captcha"></div>
<input type="submit" value="Send" />
<script type="text/javascript">
Recaptcha.destroy();
Recaptcha.create("publicKey", "captcha", {});
</script>
And the Controller is still the same
if (ReCaptcha.Validate("privateKey"))
{
}
So when it loads the view partially it executes this scripts and render correctly every time.
Thanks for the help #Bala R
I faced the same issue and the quickest solution i found is using what it is proposed above and add to it this part of code in the top of your page within the handler "EndRequestHandler" proposed by the .net javascript api ( http://msdn.microsoft.com/en-us/library/bb311028(v=vs.100)).
With this solution the backend validation always works.
Here is the code I've used :
<script type="text/javascript" language="javascript">
Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);
function EndRequestHandler(sender, args) {
if (Recaptcha != null) {
Recaptcha.destroy();
Recaptcha.create("public_key", "captcha", {});
}
}
</script>
I hope this could help someone...