getelementbyid

问题 I use a javascript to catch the x and y position when user click a link, by now, I can make it works, but I want it to return the two values to function init() when it is called. How can I do it? <script type="text/javascript"> document.addEventListener("DOMContentLoaded", init, false); function init() { var canvas = document.getElementById("canvas"); canvas.addEventListener("mousedown", getPosition, false); // how can I get the return values here? } function getPosition(event) { var x = new

问题 I use a javascript to catch the x and y position when user click a link, by now, I can make it works, but I want it to return the two values to function init() when it is called. How can I do it? <script type="text/javascript"> document.addEventListener("DOMContentLoaded", init, false); function init() { var canvas = document.getElementById("canvas"); canvas.addEventListener("mousedown", getPosition, false); // how can I get the return values here? } function getPosition(event) { var x = new

问题 This question already has answers here : Closed 8 years ago . Possible Duplicate: IE/Chrome: are DOM tree elements global variables here? I recently discovered that I can use in javascript any object from DOM with a direct reference to its id: <div id="layer">IM A LAYER</div> <script> alert(layer.innerHTML); </script> If this is true, what advantage I'd get using the getElementById method? 回答1: Accessing a DOM element directly will give you a error if the element does not exist. Wheras if you

问题 This question already has answers here : Closed 8 years ago . Possible Duplicate: IE/Chrome: are DOM tree elements global variables here? I recently discovered that I can use in javascript any object from DOM with a direct reference to its id: <div id="layer">IM A LAYER</div> <script> alert(layer.innerHTML); </script> If this is true, what advantage I'd get using the getElementById method? 回答1: Accessing a DOM element directly will give you a error if the element does not exist. Wheras if you

问题 Why is this code throwing “ TypeError : Cannot read property ' style ' of null ” ? function openNav() { document.getElementById("#sideNav").style.width = "250px"; } function closeNav() { document.getElementById("#sideNav").style.width = "0"; } <div class="sidenav" id="sideNav"> <a href="javascript:void(0)" class="closenav" onclick="closeNav()">×</a> <a href="#">Home</a> <a href="#">Listing</a> <a href="#">About Us</a> <a href="#">Contact</a> </div> <span onclick="openNav()">OPEN</span> <div

问题 I can't understand why getElementsByClassName isn't working here. n = new Date(); y = n.getFullYear(); document.getElementByClassName("date").innerHTML = y; <span class="date"></span> CompanyName 回答1: The function name is getElementsByClassName , not getElementByClassName getElementsByClassName returns an array-like object of elements, not the one of elements. Code should look like this: n = new Date(); y = n.getFullYear(); document.getElementsByClassName("date")[0].innerHTML = y; <span class

问题 I am trying to use a script on three videos using the same ID (#vid) on the same page. At the moment only one video seems to be able to use the script. var video = document.getElementById('vid') // When the 'ended' event fires video.addEventListener('ended', function(){ // Reset the video to video.currentTime = 0; // And play again video.load(); }); 回答1: Most of these answers are only partially correct. For your markup to be valid, id's need to be be unique . However, sometimes careless

问题 I am trying to use a script on three videos using the same ID (#vid) on the same page. At the moment only one video seems to be able to use the script. var video = document.getElementById('vid') // When the 'ended' event fires video.addEventListener('ended', function(){ // Reset the video to video.currentTime = 0; // And play again video.load(); }); 回答1: Most of these answers are only partially correct. For your markup to be valid, id's need to be be unique . However, sometimes careless

问题 This question already has answers here : Adding click event listener to elements with the same class (6 answers) Closed 2 years ago . I would like to use pure JS to add classes to some elements and am familiar with selecting the element with an ID, but when I've tried to use getElementsByClassName, my code breaks. Is it not possible to get elements by class name and add a new class? I know the following code works, but, again, would like to target the element by className. document

问题 I need to build an object from multiple forms input values without using jQuery. <div id="formMain"> <form id="form_id_1" class="formClass"> <div id="fullname"> <p>Full Name</p> <input type="text" class="inputClass" name="name" value="Joe"> <br/> <input type="text" class="inputClass" name="name2" value="Doe"> </div> <div id="Address"> <p>Address</p> <input type="text" class="inputClass" name="address" value="1st Maint Street"> </div> </form> <form id="form_id_2" class="formClass"> <div id=