[Chapter 15: Using Ajax]

Hey! New to these forums, but I just started web dev and about to finish the book. I am having a hard time with one thing. Well, the entire Ajax chapter is hard for me, but one part in particular I don't understand, it is a chunk of code inside the login.js for the section.

 

// Create an object of Ajax options:
    var options = new Object();

    // Establish each setting:
    options.data = data;
    options.dataType = 'text';
    options.type = 'get';

    options.success = function(response) 
    {
            // Worked:
            if (response == 'CORRECT') {

                    // Hide the form:
                    $('#login').hide();

                    // Show a message:
                    $('#results').removeClass('error');
                    $('#results').text('You are now logged in!');

            } else if (response == 'INCORRECT') {
                    $('#results').text('The submitted credentials do not match those on file!');
                    $('#results').addClass('error');
            } else if (response == 'INCOMPLETE') {
                    $('#results').text('Please provide an email address and a password!');
                    $('#results').addClass('error');
            } else if (response == 'INVALID_EMAIL') {					
                    $('#results').text('Please provide your email address!');
                    $('#results').addClass('error');
            }

    }; // End of success.
    options.url = 'login_ajax.php';

    // Perform the request:
    $.ajax(options);

1) is this line options.success = function(response) suppose to return a boolean value?

 

2) also on the same line, options.success = function(response), i am having huge problem understanding where response came from. This parameter variable is not declared anywhere or passed in, so where did it come from?

 

3) 

 

    options.data = data;

    options.dataType = 'text';

    options.type = 'get';

     ......

     options.url = 'login_ajax.php';

 

are these names, (data, dataType, type, and url) always required for ajax? or can this (or ajax in general) be done in different ways?

 

4)  $.ajax(options);

 

can you explain this more? 

 

 

 

thanks in advance guys!