How can I determine if a variable is ‘undefined’ or ‘null’?

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How do I determine if variable is undefined or null? My code is as follows: var EmpName = $(“div#esd-names div#name”).attr(‘class’); if(EmpName == ‘undefined’){ // DO SOMETHING };


Avoid browser popup blockers

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I’m developing an OAuth authentication flow purely in JavaScript and I want to show the user the “grant access” window in a popup, but it gets blocked. How can I prevent pop up windows created by …


Is ternary operator, if-else or logical OR faster in javascript?

Which method is faster or more responsive in javascript, if-else, the ternary operator or logical OR? Which is advisable to use, for what reasons?

How can I tell when changes to jquery html() have finished?

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I’m using jQuery to change the HTML of a tag, and the new HTML can be a very long string. $(“#divToChange”).html(newHTML); I then want to select elements created in the new HTML, but if I put the …

How do you edit Javascript in the browser?

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I was looking for a way to edit JavaScript in a browser, such as Firefox, on the fly and execute it. Firebug allows us to edit HTML and CSS on the fly but JavaScript is a pain. I have to go back to …

Remove links with JavaScript in browser

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How do I remove links from a webpage with JavaScript? I am using Google Chrome. The code I tried is: function removehyperlinks() { try { alert(document.anchors.length); alert(…

jQuery UI – Close Dialog When Clicked Outside

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I have a jQuery UI Dialog that gets displayed when specific elements are clicked. I would like to close the dialog if a click occurs anywhere other than on those triggering elements or the dialog …

Tags: javascript php

Go Back to Previous Page

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I am using a form to “Rate” a page. This form “posts” data to a php script elsewhere. I simply want to display a link after the form is processed which will bring the user back to previous page. Can I …

How to submit form only once after multiple clicking on submit?

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I am having problem that when i am trying to submit the form by clicking on the submit button it takes some time to post request during this if i am again click on the Submit button it will again send …


How to iterate array keys in Javascript?

I have an array created with this code: var widthRange = new Array(); widthRange[46] = { min:0, max:52 }; widthRange[66] = { min:52, max:70 }; widthRange[90] = { min:70, max:94 }; I want to get …