onchange

问题 I've got a hidden form field, and when a button gets pressed the value of the hidden field is changed. Now, I've added an observer to the hidden field, listening for changes to occur. For some reason, though, the event listener never kicks in, even though the value of the hidden element changes. I'm using Prototype and Firefox 3.6. The code looks roughly like this: button.observe('click', function(event) { hiddenField.setValue(someValue); }); hiddenField.observe('change', function(event) {

问题 Using VS 2102, .NET 4.0 and MVVM Light. I have the following code that reads items from an XML file into an ObservableCollection. I then want to update the Save button with a Converter if the collection changes (using an IsDirty flag) but the OnCodeCollectionChanged method is not being executed. The collection is properly displayed in the data grid and I can add new entries to the data grid but the OnCodeCollectionChanged method is never called. I am NOT trying to catch the change of an

问题 If I have several radio buttons of the same name, only one can be selected at any one time. When one becomes selected, any namesakes lose their selection. I'm intrigued as to why this doesn't constitute a .change() event for jQuery. Hacking the $.change() function would be pretty drastic, but this doesn't seem to be reported as a bug — so I'm interested in finding out why this isn't the case. Test below: I'd expect the two change events to fire whenever a radio is selected, but that isn't the

问题 If I have several radio buttons of the same name, only one can be selected at any one time. When one becomes selected, any namesakes lose their selection. I'm intrigued as to why this doesn't constitute a .change() event for jQuery. Hacking the $.change() function would be pretty drastic, but this doesn't seem to be reported as a bug — so I'm interested in finding out why this isn't the case. Test below: I'd expect the two change events to fire whenever a radio is selected, but that isn't the

问题 This doesn't seem to be working: <select id="mySel" onchange="alert('foo')"> <option value="a">a</option> <option value="b">b</option> </select> <script> dojo.byId('mySel').value = 'b'; // select changes, but nothing is alerted </script> (I'm using dojo, but that doesn't really matter.) 回答1: The 'onchange' name is a little misleading unless you understand that a change event and a value being changed aren't the same thing. A change event occurs when the user changes the value in the browser.

问题 This doesn't seem to be working: <select id="mySel" onchange="alert('foo')"> <option value="a">a</option> <option value="b">b</option> </select> <script> dojo.byId('mySel').value = 'b'; // select changes, but nothing is alerted </script> (I'm using dojo, but that doesn't really matter.) 回答1: The 'onchange' name is a little misleading unless you understand that a change event and a value being changed aren't the same thing. A change event occurs when the user changes the value in the browser.

问题 I am trying to do Autocomplete and onchange event at a time. Means:I want to fire onchange event in a autocomplete textbox. When i write something in the a textbox from keyboard and click outside the textbox then onchange event firing but when i select something in the from the auto suggest names onchange event is not firing. My HTML Code <div style="width: 34%"> Person Name:<input id="txt0" type="text" onchange="SaveData('txt0')" class="userSearch" placeholder="Helped Person" /> </div>

问题 <% using (Html.BeginForm() { %> <%=Html.DropDownList("TopItemsList", ViewData["ListData"], new { onchange="[???]" })%> <% } %> In the above example, what value should you set onchange to? Or, how do you get the correct form? Is there any difference with Ajax.BeginFrom? 回答1: try this: <%=Html.DropDownList("TopItemsList", ViewData["ListData"], new { onchange="this.form.submit();" })%> Every form element in the has a "form" property that is pointed to the form that contains this element. Yes,

问题 Using jquery I've added a change handler to a form. This works when any input is changed BUT only if the user manually changes an input and not when some other code changes the input. Is there any way to detect if a form has changed even if its inputs are changed by code? 回答1: Yes, there seems to be some confusion over this. In an ideal world you would expect the onchange event to happen whenever the inputs change but thats not what happens. I'm sure for good reasons to - maybe not. One way I

问题 I have the following function: function updateInput(ish){ document.getElementById("BetAmount").value = ish; } I have the following HTML inputs: <input class="defaultText" type="number" name="BetAmount" id="BetAmount" onchange="updateInput(this.value)"> <input type="number" name="PotentialGain" id="PotentialGain" /> When users enter in a bet amount number( BetAmount ), I would like to instantly show a calculated PotentialGain , which, for example, can be found by multiplying a constant by the