向远程数据库发出ajax请求[重复]

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i have built a multi search form, that queries a database, by making an ajax request, it works fine and i can query my database and display the results in a div without reloading my page.

but now i am try to query a database on a remote a server,

and i was thinking by adding the full url of the domain where the database was hosted i would be able to query the database, but i have founded out that it would take more than that.

this is what has worked for me normally

function showUser() {
    if (showUser == "") {
        document.getElementById("txtHint").innerHTML = "";

        return;
    } else { 
        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("txtHint").innerHTML = xmlhttp.responseText;
            }
        }
        var usersvalue=encodeURIComponent(document.getElementById("users").value)
var uservalue=encodeURIComponent(document.getElementById("user").value)
        xmlhttp.open("GET","getuserwrong.php?users="+usersvalue+"&user="+uservalue, true);


        xmlhttp.send();

as we can see here this was a direct connect to my php file that queries my database.

and this is what i have tried out, when trying to query my database on a remote server, that hasnt worked

function showUser() {
    if (showUser == "") {
        document.getElementById("txtHint").innerHTML = "";

        return;
    } else { 
        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("txtHint").innerHTML = xmlhttp.responseText;
            }
        }
        var usersvalue=encodeURIComponent(document.getElementById("users").value)
var uservalue=encodeURIComponent(document.getElementById("user").value)
        xmlhttp.open("GET","http://whitechapelandpartners.com/getuserwrong.php?users="+usersvalue+"&user="+uservalue, true);


        xmlhttp.send();

as we can see here i have added the domain name to where i have setup my database remotely

i am not sure what i have done wrong here, because using this method when i try to query my database on the remote server nothing happens

any usefull suggestions. Regards

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