Javascript question: Problem with calling an objects methods -

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Say I have an object called FieldEdit I define the function constructor for this object, Instant through it var obj = new FieldEdit () , and FieldEdit.prototype & Lt; Method Name & gt; = () {...} . .

Under what circumstances would other methods of this object (this. <>> Name name. ) fail?

Note that I would like to avoid posting a code sample for this, because I can think that it is a problem in my understanding of javascript compared to just a few, in fact I am pretty sure that My code is the best knowledge (and this is my knowledge, besides here the question is).

Most likely where this FieldEdit In addition to FieldEdit , the object will reference an object called nested scope such as a closure, an event handler, or any function or method explicitly .call (someOtherScope) Or .apply (someOtherScope, args) .

You must maintain a variable reference for example FieldEdit and FieldEditInstance. & Lt; Method & gt; () Instead.

. >

PrototypeJs allows you to wrap the work with function.bind for this purpose, but it can be easily accomplished otherwise, either: 

  var FieldEditInstance = this; Obj.methodThatUsesACallback (function () {// use it instead}};

or 

  var FieldEditInstance = this; Var callback = function () {// ...}; // function of prototype js which is more or less Bind has produced class bound Clawback = function (). (Return Callback. Apely (FieldEdit Instance, Arguments);}; obj.methodThatUsesACallback (boundCallback);

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