I am trying to display a "Yes / No" messagebox from codebehind in C#. I want to call an "AddRecord" procedure if the user clicks "Yes", and do nothing if the user clicks "No".
Ideally, I want to use the code below, but from codebehind:
OnClientClick = "return confirm('Are you sure you want to delete?');"
I search on SO and google, but was not able to find anything helpful.
on your Add Record button, just do the following:
<asp:button ID="AddRecordbutton" runat="server" Text="Add Record"
onclick="AddRecordButton_Click" onclientclick="return confirm('add record?');" />
In your code behind, just put the add record code in your AddRecordButton_Click event handler. It will only be called if they click Yes on the popup.
Alternatively, you could have your codebehind assign the onclientclick code when the button is initially rendered.
For example:
protected void Page_Load(object sender, EventArgs e) {
AddRecordButton.OnClientClick = #"return confirm('Add Record?');";
}
No, you don't.
You seem to be misunderstanding that basic concept of webpage.
An ASPX page is a short program, which starts-up, generates seem HTML, and then terminates. The HTML is then sent across the Internet to the users browser. EVERYTHING you do in a codebehind must be complete before the user ever sees any of it.
You really want a javascript dialog box. (Actually, from what you describe, you could just create a messagebox-looking div in HTML with a standard HTML form on it.)
To display an actual messagebox you will need javascript as it is done on the client-side. For whatever reason, if you cannot use javascript, you could do what AEMLoviji has suggested and "fake" it with some cleverness.
Note that you do not need jQuery to display a messagebox, simple javascript will suffice.
If you use the Ajax Control Toolkit Modal Popup Extender on a Panel with your two buttons this will fire an event on the server which can be handled and execute whichever method/functions you wish
See here for an example
Use RegisterStartupScript
ScriptManager.RegisterStartupScript(this, GetType(), "unique_key",
"element.onclick = function(){ return confirm('Are you sure you want to delete?'); };",
true);
To show yes/no
<script>
function AlertFunction() {
if (confirm('Are you sure you want to save this thing into the database?')) {
$('#ConfirmMessageResponse').val('Yes');
} else {
$('#ConfirmMessageResponse').val('No');
}
}
</script>
to handle it from .net side:
string confirmValue = ConfirmMessageResponse.Value;
if (confirmValue == "Yes")
{...}
Related
I'm new to web programming with .NET.
I am developing a web page with webforms, and I want at a certain moment to programmatically show a modal window, for the user to accept or cancel, according to a question. Exactly what does the "confirm" function of JavaScript.
I tried to get it calling a JavaScript function:
Page.ClientScript.RegisterStartupScript (this.GetType (), "CallMyFunction", "MyFunction()", true);
But I need to do it without reloading the page, and I also need to control if the user has accepted or canceled and I do not know how to do it.
I've also tried getting it using the ModExPopupExtender control from DevExpress.
Can someone tell me a simple way to get what I want?
I can not understand how something so usual in web programming, and that PHP + javascript would not pose any problem can be so complicated.
All start in a one-button event on the code behind:
protected void btn1_Click(object sender, EventArgs e)
{
//I make a series of checks
//If certain conditions I want to show the confirm
//According to the user has chosen ok or cancel will perform a certain action
}
Onclientclick does not help me because before launching the "confirm" I have to do some checks on the server side.
Thank you very much.
You can use OnClientClick which is a property on most web controls.
I like to just bring up a simple confirm() dialog which executes the server code if the user clicks OK and does nothing if the user cancels the action:
<asp:Button runat="server" ID="btnSave" Click="btnSave_Click" Text="Save"
OnClientClick="return confirm('Are you sure you want to do this thing?');" />
You can do other things with it as well, but the key thing to remember is that anything you do in OnClientClick will happen before the page gets posted back to the server.
This is also perfectly valid:
<asp:Button runat="server" ID="btnSave"
OnClientClick="showModalConfirm('some message goes here');" ... />
<script>
function showModalConfirm(msg)
{
$(".modal .message").innerHtml(msg);
$(".modal").Show();
}
</script>
You can set the action that OnClientClick should perform in your codebehind in exactly the same way:
protected void Page_Load(object sender, EventArgs e)
{
btnSave.OnClientClick = "return confirm('Are you sure you want to do this thing?');";
}
You can use below code in c# to call javascript function. Below code will execute afterpostback() javascript function:
ClientScript.RegisterStartupScript(GetType(), Javascript, "javascript:afterpostback();", true);
And you can write code in javascript function to display any div or popup:
<script language="javascript" type="text/javascript">
function afterpostback() {
//Here you can write javascript to display div/modal
}
</script>
One way I've handled this previously was to have 2 buttons on the page. The first would be initially visible and labeled "Submit". The second would be initially hidden and labeled "Confirm". The "Submit" button would postback upon click and perform your server side checks/validation. If those checks failed, an appropriate error message would be displayed. If those checks passed, an appropriate "Please confirm your submission"-type message would be displayed, the "Submit" button would become hidden, and the second "Confirm" button would become visible. When that Confirm button was clicked, it would postback again and fully submit.
EDIT: I forgot to mention, there's a bit more to this that occurred to me after I initially posted. You'll have to protect the fields from being edited in the event the server-side verification is successful as you obviously don't want the user changing values and then clicking the Confirm button. That means disabling all the input controls - which could be a pain if you have a lot. You also have to give them a way to (intentionally) Edit in case the server side verification passes, you display the Confirmation, and they change their minds - so basically you'd need a third "Cancel/Edit"-type button that would put the form back in edit mode and show your initial Submit button.
I have got a checkbox and want to display the confirmation message when it is clicked
I added the event binding in Code Behind file as below.
chkSMTLock.Attributes.Add("onclick", "return ConfirmSMTLock();");
The following is my HTML code for chkSMTLock
<asp:CheckBox ID="chkSMTLock" runat="server" AutoPostBack="true" OnCheckedChanged="chkSMTLock_CheckedChanged" Text="SMT Lock" />
Here is my javascript:
function ConfirmSMTLock() {
var r = confirm('Are you sure that you want to SMT lock/unlock this account?');
console.log(r);
return r;
}
When I run it, I can see the confirmation values (true/ false) in the browser console logs, but, it's not calling any server side code.
My server side code is very simple with logging...
protected void chkSMTLock_CheckedChanged(object sender, EventArgs e)
{
Utils.Debug("chkSMTLock_CheckedChanged");
}
When I remove javascript event binding for the checkbox, it executes the ServerSide event successfully. But When I put it back, it stops working.
How can I use the confirmation message box to control it?
Your validation is too far down the chain. As you've got AutoPostBack=true, you're basically submitting a form when clicking the checkbox, your validation wants to be at the form level.
Form.Attributes.Add("onclick", "return ConfirmSMTLock();");
And in ConfirmSMTLock() check the status of the checkbox to see if you need to fire the confirm dialogue. That's the simplest way I can think of.
On a side note: if you do this:
chkSMTLock.Attributes.Add("onclick", "return false;");
The checkbox becomes untickable
I have found out an answer. Since AutoPostBack = true, it will automatically send a post back to the server. So, first you need to delete that attribute from the html code.
<asp:CheckBox ID="chkSMTLock" runat="server" OnCheckedChanged="chkSMTLock_CheckedChanged" Text="SMT Lock" />
Then implement the PostBack behaviour by using the __doPostBack function of ASP.Net.
function ConfirmSMTLock() {
var r = confirm('Are you sure that you want to SMT lock/unlock this account?');
if (r == true)
{
__doPostBack("chkSMTLock", '');
return true;
}
return false;
}
Open Sasame!!!
I would like to add a Logout link to my form so our employees can log out of the job they are working on.
The code behind in my application is simple:
protected void Logout_Click(object sender, EventArgs e) {
MasterPage.Logout();
}
A asp.Button I can code by wiring up the onClick event.
How would I call this method using a asp.Hyperlink control?
You're looking for the LinkButton control. That gets rendered as an a tag, and the page will be posted back to itself so that your OnClick function can be invoked.
The Hyperlink control renders a simple hyperlink, which won't allow you to wire it up to a click handler. Try the LinkButton control instead.
Replace Hyperlink with LinkButton.
Hyperlink has no server side events.
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.linkbutton.aspx
One thing I might suggest is to simply use CSS to style your actual-fact button to adopt the look of a link, as opposed to imitating a button from something that will likely be styled differently anyway.
When imitating a button, you are relying on the user having script enabled in their browser:
The LinkButton control renders JavaScript to the client browser. The
client browser must have JavaScript enabled for this control to
function properly.
Whereas a button that is a button will submit the form.
EDIT:
As per your comment, here is a quick example you could easily adapt:
CSS:
.hyperLinkButton
{
border:none;
background:none;
color:Navy;
cursor:pointer;
}
.hyperLinkButton:hover
{
text-decoration:underline;
}
Mark-up:
<asp:Button runat="server" CssClass="hyperLinkButton"
Text="Is it a HyperLink? Is it a LinkButton? No, it's a Button!" />
Hi everyone I have a web form in which I am having a button on clicking which data back up is being taken, I used the following javascript :
<script language="javascript" type="text/javascript">
function showPleaseWait() {
document.getElementById('PleaseWait').style.display = 'block';
}
</script>
<asp:Button ID="btnTakebackup" runat="server" Text="Take Backup" Enabled="true"
onMouseDown="showPleaseWait()" CausesValidation="false" />
<div id="PleaseWait" style="display: none;">"Please Wait Backup in Progress.."</div>
Hi I am using a button to take a back up.
Now I want to show a message in btnTakebackup_Click() event, whether Back up was successful or not.
I used Response.Write("<script>alert('abcd');</script>"); in btnTakebackup_Click() event.
But the problem is that I want to show the page also, which is not showing instead white background is showing.
Thanks in advance...
To show a message box alert should be able to write out a new script to the response stream:
var script =
"<script type=\"javascript\">" +
"alert(\"Backup in progress, don't go!\");" +
"</script>"
Response.Write(script);
However much this is distasteful, I suppose it is sometimes "necessary".
You can add client side event handlers to ASP controls:
How to: Add Client Script Events to ASP.NET Web Server Controls
Cheers.
Do you really want it to be an alert? (You should know that they lock up the whole browser not just the tab your page is on), do your users really need to acknowledge the backup success by clicking ok or just be informed of it?...
I suggest you have a div on the page that says "Backup successful". The visibility of which can be set by a boolean property BackUpSuccess which you can set to true in the code behind you mention.
<div id="backUpSuccess" <%=BackUpSuccess ? "" : "style='display:none;'"%>>
Backup was successfull
</div>
...you can style the div as you like in your .css file to get attention.
If you really do want an alert you could run some JavaScript on page load to check the content of a hidden input that you set server side in similar fashion...but running javascript on page load is tricky...unless your using jQuery and then you will know it's very easy.
From your question, I understood that after clicking on the button, the data back up is happening, but the alert is not displaying as soon as you clicked the button.This is because you are calling the JavaScript in the button click event which will be fired only after all the code in the button click is executed.I suggest you to add a JavaScript function in the .aspx source page it self and call the JavaScript function as shown below:
<script ...>
function xyz()
{
alert('Please Wait');
}
</script>
and in button declaration
<asp:button id='btn_submit' runat="server" OnClientClick="return xyz();" />
Is there a way to click a link programatically, so that it has the same effects as if the user clicked on it?
Example:
I have an ASP.NET LinkButton:
<asp:LinkButton id="lnkExport" runat="server" CssClass="navclass">Export</asp:LinkButton>
I have a link on a sidebar directing to the .aspx page that has this linkbutton on it. For various reasons I can't have the code for the LinkButton executed until the page has refreshed -- so I am looking for a way to force-click this LinkButton in my code once the page is completely loaded. Is there a simple/doable way to accomplish this? If it involves triggering an event, please provide a code sample if you can. Thanks.
Triggering a click event programatically on a link will trigger the “onclick” event, but not the default action(href).
And since linkbuttons come out as hrefs, so you could try doing this with Javascript.
var lnkExport = document.getElementById('<%= lnkExport.ClientID %>');
if(lnkExport){
window.location = lnkExport.href;
}
I certainly think that, there is a design and implementation flaw which forces you to conclude as you described.
Well, invoking the click event means nothing but executing the event registration method.
So, the worst suggestion I can think of is, just call the function at what point you want to happen the click event like,
lnkExport_Click(lnkExport, new EventArgs());
Rashack's post show's how to do it. You can just do it in javascript.
function ClickLink() {
document.getElementById('').click();
}
If you want this to fire after some other event, you can add code in c# to add a call to that function on the client side when the page loads.
Page.ClientScript.RegisterStartupScript(
this.getType(),
"clickLink",
"ClickLink();",
true);
I'm not sure why you'd need your page to load if you're just wanting to programmatically click that link. I'd recommend using Response.Redirect() on the server side to redirect them to that page. Not sure if there are other extenuating reasons this simple approach won't work...
--Matt
If i understand what you're saying:
<asp:LinkButton id="lnkExport" runat="server" CssClass="navclass" onclick="lnkExport_Click">Export</asp:LinkButton>
then in your codebehind or whenever call the following when you need to...
lnkExport_Click( null, null );
and make sure you've got lnkExport_Click wired up.
protected void lnkExport_Click( object sender, EventArgs e )
{
//DO Whatever here
}
<button onclick="document.getElementById('<%=this.lnkExport.ClienID%>').click()">
click me</button>