Forums

I hava a input Node,then set an valuechange event:
input.on("valuechange", function(e) {
//doing something to change the input new Value
var newValue = myFun(e.prevVal, e.newVal);
e.target.set("value", newValue);
}, this);
as you see above, if I set the newValue does not be same with e.newVal, then the valuechange will be always run(Infinite loop).This is a sample for the question,because I have some complex logic operation with the valuechange.
So I want to halt the valuechange event,but when I call e.halt(true),it throws a exception,actually,e.halt() then calls the e._event.halt() function, but the valuechange's e object, its _event is undefined.
How can I stop valuechange event?

actually,the question is below:
input's original value is $0.00.If input non number character, the input value will be reset to e.prevVal.(no matter what to input,the initial e.prevVal is the $0.00)
when quickly input at the end of $0.00,maybe input is 'a' and 's'(this could be more characters but at least input two),then the infinit loop begin.
I print every eventchange's e status bellow:
1. e.prevVal=$0.00 e.newVal=$0.00a this is a illegal input,so i set the input value to e.prevVal($0.00),but the question become:
2. e.prevVal=$0.00a e.newVal=$0.00s as you see,i do set the input value to $0.00,but the
e.newVal is $0.00s.(character 'a' and 's' are i quickly inputed in the input),so the infinit loop begin:
//By the way, if i input the character slowly correspondly, the No.2 is:
//2. e.prevVal=$0.00a e.newVal=$0.00 correct valuechange
3. e.prevVal=$0.00s e.newVal=$0.00a
4. e.prevVal=$0.00a e.newVal=$0.00s
5. e.prevVal=$0.00s e.newVal=$0.00a
6. e.prevVal=$0.00a e.newVal=$0.00s
......
I guess after the operation(No.1 above), the e.prevVal don't have enough time to update to $0.00,the new input $0.00s has come,so the e.prevVal has still store the old value $0.00a

It sounds like you're trying to do input filtering. In that case, subscribe to the keypress event, not the valuechange event, and do /[0-9]/.test(String.fromCharCode(e.charCode)) to see if it results in a numeric character for the input. If not, e.preventDefault(). Be careful not to prevent control or navigation characters (escape, pageUp, pageDown, enter, tab, arrows) or any keypress events with e.shiftKey, e.ctrlKey, or e.metaKey. In the latter case, you'll want to test the field value for non-numerics and strip them.