Calling PHP function when link is clicked

You could possibly just use a GET statement, so it would look something like this...

HTML

<a href="download.php?init=true">Download in Excel</a>

PHP

function ExportExcel()
{
    // code
}

if($_GET['init'])
{
    ExportExcel();    
}

here is the function i implemeted recently:

$('#toexcel').live("click",function() {
            $.ajax({
                url: "toExcel.php",
                data: "sql="+encodeURIComponent(sql),
                beforeSend: function(){
                    $("#wait").show();
                },
                complete: function(){
                    $("#wait").hide();
                },
                success: function(response){
                    window.location.href = response.url;
                }
            });
        });

where sql variable actually stores sql query to the server, and then toExcel.php if getting passed sql, submitting it to the server and outputs the result using PHPExcel() object.

EDIT

i think i understood what you trying to achieve. your ExporExcel() function already outputs the results you need, right? is so, then you can do it as follow:

$('#toexcel').click(function() {
            $.ajax({
                url: "toExcel.php", // should contain and _call_ you ExportExcel() function
                beforeSend: function(){
                    $("#wait").show(); // this is loading img to show
                },
                complete: function(){
                    $("#wait").hide(); ;// this is loading img to hide once complete
                },
                success: function(response){
                    window.location.href = response.url;
                }
            });
        });

first let me make sure you know php is only parsed when the page is first being distributed. If you click a link on the page, it has no idea the php function on the same page exists because the function only existed server-side while the code was being parsed. That being said, you can easily make a separate page called download.php and call your function on that page. Then your link can just link to that page.

If you want your custom download page to return to the user as an excel file, you can use custom php headers to convince the browser that it is downloading an excel file. (you'd have to specify the MIME type for excel files)

edit: this would cause a download to start of an excel file created by your function call and activated by your link click. You don't need any JS or JQuery for this.

edit2: here's example code for the download file to get you started

<?php 
header("Content-type: application/excel");
print($data); /* print out the contents of the excel file here */
exit();
?>

If you do it like this, your php page will not redirect from your original page, but will bring up a download box from the browser instead. If your using csv files instead of xls files, you'll need to change the mime type.

you can handle the request in your js scrpit file

$("a").click(function(){
 jQuery.ajax({
    url: "path/to/controller",
    type: "POST",
    dataType: 'json',
    data: {'mentod':'ExportExcel'},
    success: successCallback,
    error:failureCallback
 });
});

Just provide link of that excel file in href of anchor , browser will download automatically If your file form DB then providelink of excel.php , and in excel.php do processing of getting excel file and creation of it . read this artical..do like that