Passing a variable from php to ajax - weird, nothing works

I am having great difficulty passing a variable from a PHP file to .js files

The code in the PHP file I used is this:

<script>

jQuery(document).ready(function(){
    var uid = <?php echo (intval($uid)); ?>;
    //var uid = <?php echo(intval($_SESSION['uid'])); ?>.val();

  });
</script>

The variable value should be passed into the .js file to refresh j开发者_如何学编程ust a certain div on the page (not the whole page) after a form submission is performed.

This is the .js file and the corresponding code starts at "// refresh the monitor list div":

    $(function() {  

   $(".button").click(function() {  
     // validate and process form here  

     $('.error').hide();  
       var domain = $("input#domain").val();  
        if (domain == "") {  
       $("label#domain_error").show();  
       $("input#domain").focus();  
       return false;  
     }  
        var com_domain = $("input#com_domain").val();  
         if (com_domain == "") {  
       $("label#com_domain_error").show();  
       $("input#com_domain").focus();  
       return false;  
     }  
        var cemail = $("input#cemail").val();
        var port = $("select#port").val();
        var active = $("input#active").val();
        var uid = $("input#uid").val();
        var main = $("select#main").val();

     var dataString = 'cemail='+ cemail + '&domain=' + domain + '&com_domain=' + com_domain + '&active=' + active + '&main=' + main + '&port=' + port;  
     //alert (dataString);return false;  
     $.ajax({  
       type: "POST",  
       url: "user_add.php",  
       data: dataString,  
       success: function() {  
         $('#monitor_form').append("<div id='message'></div>"); 
         $('#monitor_form form')[0].reset();
         $('#message').html("<img id='checkmark' src='images/tick.png' /><b> Monitor sucessfully added!</b>")  
         .hide()  
         .fadeIn(500, function() {  
           $('#message').append("");  
         });
         setTimeout("$('#message').hide().remove();", 6000);

         var dataString2 = 'ajax=1&uid=' + uid;
         $.ajax({
             type: "GET",
             url: "monpanel.php",
             data: dataString2,
             success: function(html_data){
                $('#list_monitors').html(html_data);
            }
         });
         //document.onkeydown = showDown;
       }  
     });  
     return false; 
   });  
 }); 

function showDown(evt) {
    event = (evt)? evt : ((event)? event : null);
    if (evt) {
        if (event.keyCode == 8 && (event.srcElement.type!= "text" && event.srcElement.type!= "textarea" && event.srcElement.type!= "password")) {
            // When backspace is pressed but not in form element
            cancelKey(evt);
        }
        else if (event.keyCode == 116) {
            // When F5 is pressed
            cancelKey(evt);
        }
        else if (event.keyCode == 122) {
            // When F11 is pressed
            cancelKey(evt);
        }
        else if (event.ctrlKey && (event.keyCode == 78 || event.keyCode == 82)) {
            // When ctrl is pressed with R or N
            cancelKey(evt);
        }
        else if (event.altKey && event.keyCode==37 ) {
            // stop Alt left cursor
            return false;
        }
    }
} 

function cancelKey(evt) {
    if (evt.preventDefault) {
        evt.preventDefault();
        return false;
    }
    else {
        evt.keyCode = 0;
        evt.returnValue = false;
    }
}

/*function mycallbackfunc(v,m,f) {
    if (v == 'Cancel') {
        $.prompt('The action was ' + v + 'ed');
    }
    else {
        $.prompt('Monitor ' + v + 'd successfully');
    }
}*/

// ask for validation on monitor delete, pause, resume request
$(document).ready(function(){
   $(".error").hide();  
   alert("Stage 0! -> uid="+uid.toString());
   $("#mondelpau").validate({
        debug: false,
        rules: {
            act: "required",
            uid: "required",
            sid: "required"
        },
        /*messages: {
            name: "Please let us know who you are.",
            email: "A valid email will help us get in touch with you.",
        },*/
        submitHandler: function(form) {
            // do other stuff for a valid form
            //$.post('delpaures.php', $("#mondelpau").serialize(), 
            alert("Stage 1! -> uid="+uid.toString());
            $.ajax({
              async: false,
              type: "POST",
              url: "delpaures.php",
              data: $("#mondelpau").serialize(),
              success: function(data) {
                $('#monadiv').html(data);  
                 //$('#results').html(data);
                 //alert (data);return false;

                 // refresh the monitor list div

                //$('#list_monitors').load(dataString8);
                //var uid = $("input#uid").val();
                //var dataString8 = 'ajax=1&uid=' + $("input#uid").val();
                var dataString8 = 'ajax=1&uid=' + uid; // .val()
                //var dataString8 = 'ajax=1&uid=19';
                alert("Stage 2! -> uid="+uid.toString());
                $.ajax({
                  async: false,
                  type: "GET",
                  dataType: "html",
                  url: "monpanel.php",
                  data: dataString8,
                  success: function(html_data){
                    alert("Stage 3!");
                    $("#list_monitors").css("background-color","#FF0000");
                    $("#list_monitors").html(html_data);
                  }
                });
              }   
            });
        }
    });
});

Needless to say I have tried everything, even renaming .js file to .php and redirecting to them with .htaccess, but that doesn't work either.

The reason you cannot access the variable in your js file is that the variable 'uid' is defined in a different scope than the js file. Its the same thing as:

if(true) {
    var a = 1;
}

if(true) {
    // b will be undefined since 'a' was defined in another scope
    var b = a;
}

// so
jQuery(document).ready(function({
   // this is one scope
   var a = 1;
});

jQuery(document).ready(function({
   // this is another scope and b will be undefined
   var b = a;
});

You need to store the uid in a hidden field like:

<intput type="hidden" id="hidUid" value="<?php echo (intval($uid)); ?>"/>

And then inside the scope of your javascript ($(document).ready)

var uid = $("#hidUid").val();