如何将AJAX变量传递给PHP

Question

I understand I can't pass AJAX Vars directly to PHP, being a client versus server side script. But that being said, here's my code:

setInterval(function()
{   
    //do something after you receive the result
    var xmlhttp;
    if (window.XMLHttpRequest)
    {// code for IE7+, Firefox, Chrome, Opera, Safari
    xmlhttp=new XMLHttpRequest();
    }
    else
    {// code for IE6, IE5
        xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
    xmlhttp.onreadystatechange=function()
    {
        if (xmlhttp.readyState==4 && xmlhttp.status==200)
    {
        document.getElementById("message_area").innerHTML=xmlhttp.responseText;
    }
    }
    xmlhttp.open("GET","messages.txt",true);
    xmlhttp.send();
}

I know I can indirectly process AJAX variables by POSTing them to a PHP page using AJAX, like so:

$.ajax (
{
    type: "POST",
    url: "decode.php",
}); 

I just need to know how to pass the contents of the "messages.txt" file used in the xmthttp.open call to a PHP file for further processing.

How can I do this?

Answer 1

If you are using pure javascript:

var url = "get_data.php";
var params = "lorem=ipsum&name=binny";
http.open("POST", url, true);

//Send the proper header information along with the request
http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
http.setRequestHeader("Content-length", params.length);
http.setRequestHeader("Connection", "close");

http.onreadystatechange = function() {//Call a function when the state changes.
    if(http.readyState == 4 && http.status == 200) {
        alert(http.responseText);
    }
}
http.send(params);

or if you're using jquery, simply:

$.ajax (
{
    type: "POST",
    url: "decode.php",
    params: {param1: "val1", param2: "val2"}
}); 

Answer 2

Are you using jquery? You first code block is regular js, the second is jQuery's ajax short hand.

That said, if you want to POST data with ajax using jQuery, you would do something like the following.

var PostData = "something";

$.ajax({
    type: "POST", 
    url: "someurl", 
    data: PostData
}).done(function(returnData) {
    //process data returned from server, if there is any
});

Answer 3

Hope this helps :

$.get( "messages.txt", function( data ) { //Fetching contents of messages.txt file.
    $.ajax ({
        type: "POST",
        url: "decode.php",
        data: data, //passing contents of messages.txt file to decode.php
        success: function(result){
              alert(result);//Getting result from decode.php
        }
    }); 
});

cheers