Hiding and Showing default javascript alert - javascript

How to hide and show the default Javascript alert in the same HTML Page.
For example:
In function_one I want to hide the Javascript default alert
function function_one() {
//hide Javascript alert
}
In function_two I want to show the default Javascript which has been hidden in function_one
function function_two() {
//show Javascript alert
}
Both Javascript functions are in the same HTML page.

If you want to prevent calls to alert() from being displayed, use the following code:
var defaultAlert = null;
function function_one() {
if (defaultAlert === null) {
defaultAlert = window.alert;
window.alert = function() {};
}
}
function function_two() {
if (defaultAlert !== null) {
window.alert = defaultAlert;
defaultAlert = null;
}
}

You can disable it by overriding its value with an empty function. You store the old value in a variable (oldAlert) and then restore it assigning the old value back to window.alert:
function function_one() {
oldAlert = window.alert;
window.alert = function() {};
}
function function_two() {
window.alert = oldAlert;
}

Related

Remove javascript function override

I have a java script function override that occurs when certain condition is met. How can I reset these functions to its original state if I don't need it anymore.
function setProductFields() {
if (shouldShow == 'true') {
selectField = function() {
//override
}
} else {
selectField() <--- //return to its original state
}
}
Save a reference to the old selectField in a variable, prior to changing it:
var oldSelectField = selectField;
// ... other code ...
function setProductFields() {
if (shouldShow == 'true') {
selectField = function() {
//override
}
} else {
selectField = oldSelectField;
}
}

disable function using javascript

I can not seem to find the code to disable a javascript function. What I want to do is have a javascript function and then I want to disable it. Here is the code:
<script>
var fooFunc = function fooFunction() {
alert("HELLO");
};
$(document).ready(function() {
fooFunc.disable();
});
</script>
<button onclick="fooFunc()">Button</button>
Basically, when the button is click the function should not work, it should be disabled. Thanks
"Disabling" fooFunc is the same as setting it to an empty function (not to null--that will cause an error when it is called the next time). In this case:
$(document).ready(function() {
fooFunc = function() { };
});
But I don't see how this is different from simply removing the onclick handler from the HTML element.
If you want the ability to disable/re-enable the function, you can write it like this:
fooFunc = function() {
function _fooFunc() {
if (!enabled) return;
alert("HELLO");
}
var enabled = true;
_fooFunc.enable = function() { enabled = true; };
_fooFunc.disable = function() { enabled = false; };
return _fooFunc;
}();
If you want to extend this to allow any function to be enabled/disabled, you can write a higher-order function, which takes any function as a parameter, and returns a function with enable and disable methods attached to it:
function disablable(fn) {
function inner() {
if (!enabled) return;
fn();
}
var enabled = true;
inner.enable = function() { enabled = true; };
inner.disable = function() { enabled = false; };
return inner;
}
Now you can define fooFunc as
var fooFunc = disablable(function fooFunction() {
alert("HELLO");
});
and the rest of your code will work as you want.
You can access the onclick property of the element..
<button id="id" onclick="fooFunc()">Button</button>
<script>
document.querySelector('#id').onclick = '';
</script>
If you don't want the function to work at all and be totally disabled then use the below.
If you want the function to work only under certain conditions then you will need if/else statements so it will work only when the conditions that you have set are met.
$(document).ready(function(){
$("button").onclick(function(event){
event.preventDefault();
});
});
You were going to define it back to undefined or null.
fooFunc=undefined;
You Should be doing this :) Change function definition on very first run and you are good to go.
<! DOCTYPE html>
<html lang="en">
<body>
<script>
var fooFunc = function() {
alert("HELLO");
fooFunc = function(){};
};
var enablefooFunc = function()
{
fooFunc = function() {
alert("HELLO");
fooFunc = function(){};
};
}
</script>
<button onclick="fooFunc()">Run once and Disable FooFunc</button>
<button onclick="enablefooFunc()">Enable FooFunc</button>
</body>
</html>

Trigger addEventListener on live element that is not in the DOM (native JavaScript)

I'm stuck with my modal popup plugin since a week.
I'll try to explain as much as i can but first, here is the jsfiddle: http://jsfiddle.net/hideo/yth37hhf/27/
I know the code contains some other functions but they are useful for my plugin.
So, my issue is that the function "triggerLinkAction" contains an addEventListener which is not fired.
(function() {
Window.prototype.triggerLinkAction = function(){
var triggeredLink = document.getElementById("triggeredOtherAction");
var inputTarget = document.getElementById("inputText");
console.log('triggeredLink',triggeredLink);
triggeredLink.addEventListener("click", function (e) {
alert('If this pops out, I will be very happy!!!');
e.preventDefault();
inputTarget.value = "This text should be on the input field...";
}, true);
}
})();
The targeted element is inside the modal, and this modal is displayed by clicking on the link "A small modal".
When the plugin calls ShowModal(), I trigger the TransitionEnd event to call a function
[.... code ...]
function ShowModal() {
vars.popupContainer.classList.add("show");
hsdk.PrefixedEvent(vars.popupOverlay, "TransitionEnd", function (e) {
executeFunctions();
});
}
[.... code ...]
The executeFunctions() will check which functions need to be called:
[.... code ...]
function executeFunctions() {
if (vars.opts && vars.opts.fn) {
var allFunctions = vars.opts.fn.split(',');
for (var i = 0; i < allFunctions.length; i++)
{
var functionName = allFunctions[i];
var functionToExecute = window[functionName];
if(typeof functionToExecute === 'function') {
functionToExecute();
}
}
}
}
[.... code ...]
There are some comments on the javascript part about the plugin, but feel free to ask if I can provide any other information.
PS: I don't care about IE for now ;-)

Prompt popup in bootbox is not closing

The prompt popup that occurs when I click the button with class 'alert3' does not close.
CLICKMEMEMEMEMEME
and this is the function that I am invoking:
<script>
$(document).on("click", ".alert3", function(e) {
bootbox.prompt("What is your name?", function(result) {
if (result === null) {
Example.show("Prompt dismissed");
} else {
Example.show("Hi <b>"+result+"</b>");
}
});
});
</script>
The popup does not close because you have an error in the callback function, so it crashes before bootbox can make the popup disappear.
The best guess is that Example is not defined in your code. Maybe you took it on the Bootbox website, they are using a javascript object called Example.
If you want to show the result with your callback function, you can add this to your html:
CLICKMEMEMEMEMEME<br/>
<p id='result'></p>
And then change your javascript:
<script>
$(document).on("click", ".alert3", function(e) {
bootbox.prompt("What is your name?", function(result) {
if (result === null) {
$('#result').html("Prompt dismissed");
} else {
$('#result').html("Hi <b>"+result+"</b>");
}
});
});
</script>
Prompt popup in bootbox.js
That is not working because Example function is not defined there.We need to first defined them that using current selector value and text associated with them.here $("#result") is used to show error message in particular div.
html code:
<p>Click here-><a class="alert" href=#>Alert!</a></p><p id='result'</p>
code:
var Example = (
function()
{
"use strict";
var elem,
hideHandler,
that = {};
that.init = function(options) {
elem = $(options.selector);
};
that.show = function(text) {
clearTimeout(hideHandler);
$("#result").html(text);
$("#result").fadeIn();
hideHandler = setTimeout(function() {
that.hide();
}, 4000);
};
that.hide = function() {
$("#result").fadeOut();
};
return that;
}());

ajax $.get callback reported as undefined

I have defined a div within which a form with default input values is appended based on MySQL table data returned by PHP via an ajax $.get call.
The div looks like:
<div id="esfContainer1">
</div> <!--end esfContainer1 div-->
The div is absolutely positioned relative to the body tag.
The script associated to the form validation broke when it was included on the main page where the call to the form was being made, so I moved it to the PHP output $formContent.
Here is the form validation and submit script included in the PHP output:
<script type="text/javascript">
var senderName = $("#sendName");
var senderEmail = $("#fromemailAddress");
var recipientEmail = $("#toemailAddress");
var emailError = $("#esemailerrorDiv");
senderName.blur(checkName);
senderEmail.blur(checkSEmail);
recipientEmail.blur(checkREmail);
function checkName() {
if (senderName.val() == "YOUR NAME") {
$("#esemailerrorText").html("Please provide your name");
$(emailError).removeClass("esemailError");
$(emailError).addClass("esemailErrorNow");
$(emailError).fadeIn("fast","linear");
$(emailError).delay(2000).fadeOut("slow","linear");
return false;
} else {
return true;
}
};
function checkSEmail() {
var a = senderEmail.val();
var filter = /^([\w-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
if (filter.test(a)) {
return true;
} else {
$("#esemailerrorText").html("Please enter a valid email address");
$(emailError).removeClass("esemailError");
$(emailError).addClass("esemailErrorNow");
$(emailError).fadeIn("fast","linear");
$(emailError).delay(2000).fadeOut("slow","linear");
return false;
}
};
function checkREmail() {
var a = recipientEmail.val();
var filter = /^([\w-\.]+)#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$/;
if (filter.test(a)) {
return true;
} else {
$("#esemailerrorText").html("Your friend\'s email is invalid");
$(emailError).removeClass("esemailError");
$(emailError).addClass("esemailErrorNow");
$(emailError).fadeIn("fast","linear");
$(emailError).delay(2000).fadeOut("slow","linear");
return false;
}
};
$("#emailForm").submit (function() {
if (checkName() && checkSEmail() && checkREmail()) {
var emailerData = $("#emailForm").serialize();
$.get("style.php",emailerData,processEmailer).error("ouch");
function processEmailer(data) {
if (data=="fail") {
return false;
} else if (data=="pass") {
$("#c1Wrapper").fadeOut("slow","linear");
$("#confirmation").fadeIn("slow","linear");
$("#esfContainer1").delay(2000).fadeOut("slow","linear");
$("#backgroundOpacity").delay(2000).fadeOut("slow","linear");
return false;
}
};
return false;
};
return false;
});
I have splatter-bombed the above submit function with "return false;" because the submit function has been simply opening the processing PHP script rather than executing the $.get. Watching the submit function with Firebug reports that processEmailer is undefined.
I am very new to this. I was assuming that because the ajax callback is being defined within the submit function (and that the processEmailer function is defined directly below the ajax call) that there wouldn't be a problem with definition.
Thanks in advance for any help.
You've been trapped by function statements. Function declarations (which would be hoisted) are not allowed inside blocks (if/else/for bodies) and if they are appear there, behaviour is not defined. Firefox defines them conditionally, and in your case after you've used it in the $.get call - where it was undefined then - like in var functionName = function() {} vs function functionName() {}.
To solve this, simple put it outside the if-block (or even outside the whole callback). Btw, .error("ouch") won't work, you need to pass a function.
$("#emailForm").submit (function() {
if (checkName() && checkSEmail() && checkREmail()) {
var emailerData = $("#emailForm").serialize();
$.get("style.php",emailerData).done(processEmailer).fail(function() {
console.log("ouch");
});
}
return false;
// now a proper function declaration, will be hoisted:
function processEmailer(data) {
if (data=="fail") {
return false;
} else if (data=="pass") {
$("#c1Wrapper").fadeOut("slow","linear");
$("#confirmation").fadeIn("slow","linear");
$("#esfContainer1").delay(2000).fadeOut("slow","linear");
$("#backgroundOpacity").delay(2000).fadeOut("slow","linear");
return false;
}
}
});

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