onchange | 易学教程

jQuery: adding change event handler with predefined function

阅读更多关于 jQuery: adding change event handler with predefined function

So I have the following: var change_handler = function(element) { // ... do some fancy stuff ... } Now, I want to attach this to an element. Which is the better/best or more correct method? $('element_selector').change(change_handler(this)); Or... $('element_selector').change(function() { change_handler(this); }); And does it make any difference if you're passing the object to the function or not? Neither.. $('element_selector').change(change_handler); change_handler will be the so to speak pointer to the method and the argument of the element is already passed by jQuery If you were to use $(

react.js change input value with javascript

阅读更多关于 react.js change input value with javascript

问题 I would like to change the values with javascript/jquery but when I hit submit, the old initial values are used and not my new ones. I cannot change the react code, I can only change the values with javascript/jquery as shown below. var value = "randomIntValue"; $("input[data-reactid='.0.2.0.0.0.0.0.2.0.0.3.0.3.0.0']").val(value).change(); The above code doesn't work! 回答1: From what I can gather from the comments above, the problem you're having is that you're trying to change a React

Javascript select drop down menu onchange not firing properly

阅读更多关于 Javascript select drop down menu onchange not firing properly

问题 my onchange isn't firing the javascript method properly. Select code (in HTML file) <select id="crit_1" onchange="crit1Update()"> <option value=null>Criteria 1</option> <option value="major">Major</option> <option value="grad">Graduation Year</option> </select> crit1Update() code (in external filter.js file in same folder as HTML file containing the above with the following code in head of HTML <script type="text/javascript" src="filter.js"> </script> function crit1Update() { var crit1 =

HTML table onChange

阅读更多关于 HTML table onChange

问题 I have a problem: I have table that is updated from time to time by AJAX script. This update is called from Chrome plugin which I don't want to change. So I'd like to add some kind of jQuery trigger that on change of table cells will call my own function. Is it possible? I tried event onChange but it doesn't work (it's for input if I'm right) Thanks in advance! 回答1: onchange is designed for use with inputs like <select> - so wont work in this context. There are specific dom related events you

Javascript manually firing .onchange() event

阅读更多关于 Javascript manually firing .onchange() event

问题 I have an input field I want to assign a new value and fire an .onchange() event. I did the following: document.getElementById("range").value='500'; document.getElementById("range").onchange(); Where range is my input Id. I get the following error: Uncaught TypeError: Cannot read property 'target' of undefined Is there a way to define the 'target'? Thank you 回答1: The error about target is because there's code in the event handler that's trying to read the target property of the Event object

javascript file input onchange not working [ios safari only]

阅读更多关于 javascript file input onchange not working [ios safari only]

问题 The code below works everywhere except on safri mobile. Apparently the onchange is never triggered. // create a hidden file input element var input = document.createElement("input"); input.type = "file"; // when the input content changes, do something input.onchange = function(event) { // upload files } // Trigger file browser input.click(); I have found similar examples however they all refer to scenarios where there is even a form of some other visible representation of the file input and

Delphi TListBox OnClick / OnChange?

阅读更多关于 Delphi TListBox OnClick / OnChange?

问题 Is there a trick to getting "OnChange" type of functionality with a TListBox? I can subclass the component and add a property, etc then only carry out OnClick code if the Index changes... I can also hack it with a form level variable to store the current index but just wondering if I'm overlooking the obvious before I go one way or the other. 回答1: There seems to be no way other than implementing this by yourself. What you need is to remember the currently selected item and whenever the

Trigger Change event and keyup event in select element

阅读更多关于 Trigger Change event and keyup event in select element

问题 I have some codes that should be run when a select element changes.I do it with jquery in this way: $("#myselect").change(function() { ....... }); But I want these codes run also when user change the select using keyword arrows. As i found the event for this purpose is 'keyup' . So will be : $("#myselect").keyup(function() { ....... }); How can i combine these two event? 回答1: You can use .bind() to combine them: $("#myselect").bind("change keyup", function(event){ //Code here }); See

Does a form reset button fire a select elements onChange event?

阅读更多关于 Does a form reset button fire a select elements onChange event?

问题 I have a form with some select elements that have onChange events attached to them. I would like the event to fire even when someone clicks the form reset button. My question is: does resetting a form fire a select elements onChange event? Here is a simple example in jQuery <script type="text/javascript"> $('.myselect').change(function() { // do something on change }); </script> <form action="/" method="post"> <select class="myselect" name="select1"> <option value="1">First</option> <option

Jquery select change

阅读更多关于 Jquery select change

问题 <select id="Nazione" name="Nazione"> <option prefix='+93' value='AF' >Afghanistan </option> <option prefix='+355' value='AL' >Albania </option> <option prefix='+213' value='DZ' >Algeria </option> <option prefix='+376' value='AD' >Andorra .... etc </select> and this js $(document).ready(function() { $('#Nazione').change(function(){ alert( $(this).find("option:selected").attr('prefix') ); alert( $(this).attr('prefix') ); }); }); I have alert NULL... WHy? 回答1: Your code is fine. Here's a demo :