Question

I am not a professional java script programmer. I hope you can help me.

I wrote a code to list port status using ajax. for example site:google.com ports: from 24 to 80 . But it is not working while I try to use a Javascript For Loop to list the output.
code is[index.php]:

<div id="inputform"><span>Enter URL or IP</span>
  <input type="text" name="urladress" id="urladress" size=25 maxlength=100 value="<?php if (isset($_POST['urladress'])){echo $_POST['urladress'];}; ?>"></br>
  from port
  <input type="text" name="fromport" id="fromport" size=5 maxlength=6 value="<?php if (isset($_POST['fromport'])){echo $_POST['fromport'];}else{echo "1";} ; ?>">
  to:
  <input type="text" name="toport" id="toport" size=5 maxlength=6 value="<?php if (isset($_POST['toport'])){echo $_POST['toport'];}else{echo "24";} ;; ?>">
  <input type="button" value="submit" onClick="getresults();" class="btn">
</div>
<div id="result" name="result"> </div>
<script language="javascript" type="text/javascript">
    // Get the HTTP Object
    function getHTTPObject(){
        if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");
            else if (window.XMLHttpRequest) return new XMLHttpRequest();
        else {
            alert("Ajax not supported.");
            return null;
        }
    }
    // Change the value of the outputText field
    function setOutput(){

        document.getElementById('result').innerHTML += httpObject.responseText;

    }
    // Implement business logic
    function getresults(){
        document.getElementById('result').innerHTML = "calculating</br>"
        httpObject = getHTTPObject();
        if (httpObject != null) 
        {
            var fromport = document.getElementById('fromport').value;
            var toport = document.getElementById('toport').value;
            if (fromport>toport || toport=='' || fromport==''){alert('wrong values');return 0;}

            for(var i=fromport;i<=toport;i++){
                httpObject.open("GET", "portscanner.php?inputText="+document.getElementById('urladress').value+"&port="+i, true);
                httpObject.send(null);
                httpObject.onreadystatechange = setOutput;
            }

        }
    }
    var httpObject = null;
    </script>
</div>

server side[portscan.php]:

<?php
if (isset($_GET['inputText'])){
    $url=$_GET['inputText'];
    $url = str_replace("http://","",$url);
    $url = str_replace("www.","",$url);
    $port=$_GET['port'];
    $fp = @fsockopen($url,$port,$errno,$errstr,2);
    if(!$fp)
    {
        echo "port #". $port . "is closed</br>";
    }
    else
    {
        echo "Port #".$port."is open.</br>";
        fclose($fp);
    }
};
?>

it just shows last port’s result:
for example site:http://stackoverflow.com ports: from 70 to 80 shows:

calculating
Port #80is open.
Port #80is open.

it should look like:

calculating
Port #70is closed.
Port #71is closed.
Port #72is closed.
...
Port #79is closed.
Port #80is open.

Answer 1

httpObject will be overridden each time your loop executes. You probably need an array of httpObjects to handle this.

OnReadyStateChange is not a blocking command so the FOR loop will continue until the last time.

Change functions like this :

// Change the value of the outputText field
function setOutput(index){
    if(this.readyState == 4) // Done
    {
        if(this.status == 200)
            document.getElementById('result').innerHTML += this.responseText;
        else
            document.getElementById('result').innerHTML += "Error occured : " + this.status + "<br>";
    }
}
// Implement business logic
function getresults(){
    document.getElementById('result').innerHTML = "calculating</br>";
    var fromport = document.getElementById('fromport').value;
    var toport = document.getElementById('toport').value;
    if (fromport>toport || toport=='' || fromport==''){alert('wrong values');return 0;}

    for(var i=fromport;i<=toport;i++){
        var index = httpObject.push(getHTTPObject()) - 1;
        httpObject[index].open("GET", "test.php?inputText="+document.getElementById('urladress').value+"&port="+i, true);
        httpObject[index].send(null);
        httpObject[index].onreadystatechange = setOutput;
    }
}
var httpObject = new Array();