先前对象无法使用的处理程序。 只有最后一件作品

Question

I want to return a new handler every time for a new object that I create. This handler takes one object argument.

function abc () {
    var handle = function(position) {
        // some code goes here
    };
    var obj1 = new SomeOBJ ();
    obj1.handler = handle;
    return obj1;
}

When I create one object it works fine, but when I create another object the previous handler doesnot work anymore, only the latest object's handler works.

For me it looks like the latest only one handle is being created and is attached to the latest object every time.

What can be the reason for this?

Thank you.

Answer 1

I can't figure out what you exactly are trying to do and what you are doing. If you are trying to have separate methods on each instance of a class you can assign the method on initialize or after the init function:

function Klass() {
    // Assign a specific method for each instance of this class:
    this.handler = function() {};
}
// This method is the same around all instances of this class:
Klass.prototype.otherMethod = function() {};
// Create three instance of the class to compare:
var klass = new Klass();
var klass2 = new Klass();
var klass3 = new Klass();

// See the handler method is different on each instance:
console.log(klass.handler === klass2.handler); // false;
// And the methods set through the prototype is shared:
console.log(klass.otherMethod === klass2.otherMethod); // true;

// Give klass3, klass2's handler:
klass3.handler = klass2.handler;
// These are shared as well because of what we just did.
console.log(klass2.handler === klass3.handler); // true;

klass3.otherMethod = function() {};
// Because klass3 have got another method assigned to 'otherMethod' this will return false
console.log(klass2.otherMethod === klass3.otherMethod); // false;