Prevent webform postback onclick button - asp.net

I have a webform with an asp button that when clicked, needs to perform a function in c#. The function does not affect anything on the page so I do not need a refresh of the page.Is there any way to prevent an asp button from doing a postback? I am not familiar at all with JavaScript so I need to perform this function in c#. Surely there is a way. I have researched but nothing works. CausesValidation="false"' does not work. UseSubmitBehavior=false does not work. And neither does setting the OnClientClick to return false. Keep in mind I am not using JavaScript. Anyone know how?

Add a ScriptManager in your Page first,
Then add an update panel which will have all the controls. This will prevent the entire page being posted back.
here goes an example
<asp:ScriptManager ID="MainScriptManager" runat="server" />
<asp:UpdatePanel ID="pnlHelloWorld" runat="server">
<ContentTemplate>
<asp:Label runat="server" ID="lblHelloWorld" Text="Click the button!" />
<asp:Button runat="server" ID="btnHelloWorld" OnClick="btnHelloWorld_Click" Text="Update label!" />
</ContentTemplate>
</asp:UpdatePanel>

If you do not want to monkey with the ScriptManager or the server side stuff, you can always use an HTML control as in:
<input type="button" id="myButton" value="Do Something" onclick="doSomeFunction(); return false;" />
OR
<button id="myButton" onclick="doSomeFunction(); return false;">Do Something</button>
I did discover that attaching the click event to a button element via jQuery will result in a postback (at least that's what happened to me), so I switched to the tried and true input element.

Related

ASP.NET Webforms OnClientClick without enter submission

I have the following command button:
<asp:Button Text="Insert Value" UseSubmitBehavior="false" runat="server" OnClientClick="return Confirmation.value('insert');" CommandName="Insert" />
I am using UseSubmitBehavior="false" to prevent ASP.Net page enter key causing post back
I do not want to listen to the enter keyCode via javascript because enter is used to submit non-webform elements not related to the form
Apparently, when using a Command and UseSubmitBehavior="false" then OnClientClick doesnt work. If I turn on submit behavior it works as expected but then hitting enter on the page automatically tries to click the button.
I prefer not to listen for the click event in Jquery or in javascript, and prefer a webform solution. Possible a better way of prevent enter from submitting the form or a way for OnClientClick to work properly with no submit behavior
You may need to use Panel and keep all your form inside Panel Tag and set the DefaultButton value of Panel to Button. Like Below:
<asp:Panel ID="Panel1" runat="server" DefaultButton="Button1">
// other form elements
<asp:Button Text="Insert Value" ID="Button1" runat="server" OnClientClick="return Confirmation.value('insert');" />
</asp:Panel>

ASP.NET Button submits page and I can't stop it

I have a simple proof of concept web page. It uses one master page and one content page, the default one, default.aspx. I'm doing some client side debugging with alert boxes. I dragged an asp.net button onto the page and set CausesValidation = false and UseSubmitBehavior = false and yet when I click it the page submits.
What am I doing wrong?
Here is a design time code....
<asp:Button ID="Button1" runat="server" Text="Button" UseSubmitBehavior="False" CausesValidation="False" />
Here is Runtime render, wth is it putting in a PostBack?
<input type="button" name="ctl00$ContentPlaceHolder1$Button1" value="Button" onclick="javascript:__doPostBack('ctl00$ContentPlaceHolder1$Button1','')" id="ContentPlaceHolder1_Button1" />
--Update--
Thanks Volkan Paksoy, that worked. For those who suggested HTML buttons, that worked too and that is what I used, but I was just curious why the ASP.NET button wouldn't work. It's something I should know and probably something I knew and forgot. Thanks for the help
If you need to use asp:Button and disable submit you can add OnclientClick function such as:
<asp:Button ID="Button1" runat="server"
CausesValidation="False"
OnClick="Button1_Click"
Text="Button"
UseSubmitBehavior="False"
OnClientClick="return false;" />
This should stop the postback. But you can simply use an input too of course. This is just one way of doing it.
If you want to create a button that does not submit the page/postback to the server, you could create one using raw HTML like so:
<input type="button" />

Form Validators firing on Umbraco

We are developing a web application in Umbraco 4 and have come across an intermittent problem when posting data between pages. When a form submission is posted to a new page all of the validators are firing causing various unwanted results, we have tried various posting methods using different buttons with the same result. Has anyone else come across this issue?
The validation group is working but I got to the bottom of the issue.
One of the submit buttons on the page was a html submit, with no runat server, so the code-behind didn't know where the submit had come from, so all validations where fired, regardless of validation group
All postbacks events, unless otherwise specified, will cause all validators on a page to be triggered. Either...
A) Set the ValidationGroup property on each of the validators as well as the control which you do want to trigger validators to the same name.
<asp:RequiredFieldValidator ID="valName" runat="server" AssociatedControlID="txtName" ValidationGroup="AllRequired" />
<asp:TextBox ID="txtName" runat="server" />
<asp:Button ID="btnSubmit" runat="server" ValidationGroup="AllRequired" OnClick="..." />
<asp:Button ID="btnSkip" runat="server" OnClick="..." />
In this case, btnSkip won't trigger the validators.
B) Set the CausesValidation property on the control which you don't want to trigger validation to false.
<asp:Button ID="btnSubmit" runat="server" CausesValidation="false" OnClick="..." />

validation problem in asp.net

I am using Page.Isvalid function in my web page.I have two buttons in my web page namely "save" and "generate".when i click the save button the validation summary will be invoked in which all the validations in this page will be shown.
Now I dont want to show a particular validation message for the "Save" button, but the same validation message should be shown specifically to "generate" button in the same page.
But i am using Page.Isvalid in the "save" button click which is displaying all the validation messages in the page.
Any help would be deeply appreciated.Thanks
You can use ValidationGroup(s) to do this.
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server" />
<asp:RequiredFieldValidator ID="R1" runat="server"
ErrorMessage="*"
ValidationGroup="GenerateOnly"
ControlToValidate="TextBox1" />
<asp:Button ID="Generate" runat="server" Text="Generate"
ValidationGroup="GenerateOnly" />
<asp:Button ID="Save" runat="server" Text="Save" />
</div>
</form>
This example triggers the validator if Generate is clicked, but not when Save is clicked, and also works when calling Page.IsValid in the buttons onclick function.
not entirely sure what you mean but here goes.
If you want both the save and generate buttons to generate validation messages then why not move the Page.Isvalid along with the validation code into another method. Call this method from both the save and generate methods.
If I've got the wrong end of the stick please let me know a bit more.
Cheers Tigger
Ya buddy if you have to call the same function for two different buttons it is not possible without the concept of overloading. Otherwise you have to create two methods.
But I'am not sure as i am a begginer

queue asp.net UpdatePanel postbacks

is there a way to queue postbacks with UpdatePanel?
I have a form with many textboxes. each textbox is wrapped inside it's own UpdatePanel with AutoPostBack set to true. so, when textbox changes, postback occurs.
viewstate is disabled (so do not need to worry about it).
the problem appears when user changes one text box and then quickly tabs to the next text box, changes it, and tabs again. some of the postbacks are getting lost and I want to avoid that.
You can get a client-side "hook" when the update panel is about to fire. This means that you could, at least, temporarily disable the text boxes (or have some sort of 'please wait' notification) while the update panel is refreshing.
The following snippet of ASP.NET/Javascript shows how to intercept the update panels firing and disable the textboxes.
<form id="form1" runat="server">
<asp:ScriptManager runat="server"></asp:ScriptManager>
<div>
<asp:UpdatePanel runat="server" ID="updatePane1">
<ContentTemplate>
<asp:TextBox runat="server" ID="textBox1" AutoPostBack="true" OnTextChanged="textBox_TextChanged" />
</ContentTemplate>
</asp:UpdatePanel>
<br />
<asp:UpdatePanel runat="server" ID="updatePane2">
<ContentTemplate>
<asp:TextBox runat="server" ID="textBox2" AutoPostBack="true" OnTextChanged="textBox_TextChanged" />
</ContentTemplate>
</asp:UpdatePanel>
<br />
</div>
</form>
<script type="text/javascript">
Sys.WebForms.PageRequestManager.getInstance().add_initializeRequest(InitializeRequest);
function InitializeRequest(sender, args) {
if (args._postBackElement.id == 'textBox1' || args._postBackElement.id == 'textBox2') {
document.getElementById('textBox1').disabled = true;
document.getElementById('textBox2').disabled = true;
}
}
</script>
I know this isn't exactly what you originally asked for ("is there a way to queue postbacks with UpdatePanel"), but the net effect is that it forces the user to queue up their requests so no more than one is being processed at a time. You can probably amend this to something more elegant too.
There's no built in way to control this. jQuery has some pretty nifty stuff that makes AJAX calls pretty simple. You might try looking into handling your own postbacks that way.
I know, this is not a answer to your question. But I would recommend a re-think, if you really need to wrap each text box with an update panel. Update panels are useful but you need to be careful in their usage. An plain jQuery Ajax solution may be better in your scenario.

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