Accessing Object's Internal Properties?

Mar 31, 2011

I am fairly familiar with the concept of Objects and their properties and methods, but javascript being object based as opposed to object oriented has me stumped on how to access an object's properties from an onclick event handler created for another object created within the original object.In the example below, I have a constructor function called anyObj. to which I pass an object reference to an element.

anyObj has 3 properties and one function increaseWidth()

increaseWidth() creates a new button with an onclick event handler and this is where I have a problem.The onclick function needs to increase the value of anyObj's this.width property. I originally had a line this.width += 10; in the onclick but quickly realised why this wasn't working because the this in the onclick function refers to the new button object and not the this.width property of anyObj.

The workaround I have used, and it works, is to make a copy of all the this.xxxxx properties. eg. width = this.width; and use the width variable in the onclick as you can see below. This "workaround" works fine but doesn't feel ideal to me.So, what I am asking advice on is, is there a better way to access the anyObj()'s properties from within the onclick function than the way I have done it? Obviously I would prefer to not have to make copies of all the anyObj() properties like I have to make them accessible to the onclick function.

Code:

function anyObj(divObj){
this.elem = divObj;
this.width = 50;

[code]....

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Way To Access Object's Internal Properties

Apr 1, 2011

I am fairly familiar with the concept of Objects and their properties and methods, but javascript being object based as opposed to object oriented has me stumped on how to access an object's properties from an onclick event handler created for another object created within the original object.

In the example below, I have a constructor function called anyObj. to which I pass an object reference to an element.

anyObj has 3 properties and one function increaseWidth()

increaseWidth() creates a new button with an onclick event handler and this is where I have a problem.

The onclick function needs to increase the value of anyObj's this.width property. I originally had a line this.width += 10; in the onclick but quickly realised why this wasn't working because the this in the onclick function refers to the new button object and not the this.width property of anyObj.

The workaround I have used, and it works, is to make a copy of all the this.xxxxx properties. eg. width = this.width; and use the width variable in the onclick as you can see below. This "workaround" works fine but doesn't feel ideal to me.

So is there a better way to access the anyObj()'s properties from within the onclick function than the way I have done it? Obviously I would prefer to not have to make copies of all the anyObj() properties like I have to make them accessible to the onclick function.

function anyObj(divObj){
this.elem = divObj;
this.width = 50;
this.height = 50;

[Code]....

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[code]....

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[code]....

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[Code]...

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Code JavaScript:
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Subject line would seem to say it all:

How does one trigger the execution of a method within an object or any
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More elaboration for those who want it:

Suppose we have anObjectType, with a property .description, whose value
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When an instance of anObjectType is created, the value of description is
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But the property .description is not merely read-only. Fetching the value
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When .description is set with a value of type string, the string is
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