Salesforce使用Jquery将数据从visualforce页面发送到apex控制器

Question

I am new to Salesforce and have a question on VisualForce pages (VF) and Apex Controllers.

If i have a VF page with a controller included in it, then when the page loads, a new instance of the controller will be created on SFDC. Is this correct?

if correct, then the Controller will have some state having some variables which holds some data. If i want to access a VF page which also had the same controller included in tag, then will that VF page can access the same info of the same controller instance or will that create a new instance of that controller ?

I came to know that using can be used to make ajax calls to the controller which sends the view state from client and updates the viewstate when response comes to browser. But, Salesforce(SFDC) sends lots of junk when i use . I don't want all this junk. i just need to send a small JSON string from controller.

I am trying to use the JQuery AJAX call to some VF page which is also having the same controller included. My doubt is whether it uses the same instance of that controller or will that create a new instance?

Answer 1

you can use RemoteAction

global with sharing class myController{
    @RemoteAction
    global static string foo(String str) {
        return 'OK';
    }
}

On Page

<script>
myController.foo('str',callBack)

function callBack(res){
  alert(res);
}
</script>