Question

I am using ajax to connect to a PHP script and then retrieve the graph coordinates needed for the jqplot jQuery graphing library.

The problem is that I am having difficulties constructing a proper PHP array that can then be converted into a jQuery array that jqplot can read.

Here is the code that retrieves the array from the PHP file:

$.ajax({
    type: 'POST',
    dataType: "json",
    url: "behind_curtains.php",
    data: {
        monthSelected: month_option_selected
    },
    success: function (data) {
        var stored_data = data;
        alert(stored_data);
    }
});
return stored_data;
}

Here is the code that creates the jqplot

jQuery.jqplot('chartdiv-data', [], {
    title: 'Plot With Options',
    dataRenderer: stored_data,
    axesDefaults: {
        labelRenderer: jQuery.jqplot.CanvasAxisLabelRenderer
    },
    axes: {
        xaxis: {
            label: "Day",
        },
        yaxis: {
            label: "data"
        }
    }
});

If you could please help me create the proper data array in the behind_curtains.php file it would be great!

Edit 1
the graphing coordinates array should be in the form of:

[[[1,2],[3,5],[5,13]]]

and basically I need to somehow write php code that can output an array that stores data in that form.

Thanks

Solution:

*behind_curtains.php*

I put together an array that simply generates a string in the form of [[1,2],[3,5],[5,13]]. I then stored the string in a variable and echoed that variable in the form of:

echo json_encode($stored_data);

On the user side of things here is how my code looked like:

<script type="text/javascript">
$("document").ready(function() {
        $.ajax({
            type: 'POST',
            dataType:"json",
            url: "behind_curtains.php",
            data: {
                monthSelected: month_option_selected},
            success: function(data){                    
            var stored_data = eval(data) ;  
/* generate graph! */
$.jqplot('chartdiv-weight', [stored_data], {
 title: month, 
axesDefaults: {
    labelRenderer: jQuery.jqplot.CanvasAxisLabelRenderer
  },
  axes: {
    xaxis: {
      label: "Day",
    },
    yaxis: {
      label: "data"
    }
  }   
});
        }
        });
    }

}});</script>

I hope that helps, if no, whoever is interested please let me know.

Answer 1

You can return the stored_data but you need to have it declared before the AJAX call, like shown in the bottom most example, here. You must also use: async: false otherwise you cannot return your data in this fashion. For the same reason if you like you could use getJSON() instead.

As it goes to formatting your retrieved data a similar issue I answered here. You need to build your array accordingly to represent your data.

If you can show how exactly does your JSON look like then I could give you a more precise answer.