function get(obj) {
  var poststr = "sort=" + encodeURI( document.getElementById('sort').value ) +
    "&dynamic=" + encodeURI('true') +
    "&returnpage=" + encodeURI( document.getElementById('returnpage').value ) +
    "&category=" + encodeURI( document.getElementById('category').value ) +
    "&length_min=" + encodeURI( document.getElementById('length_min').value ) +
    "&length_max=" + encodeURI( document.getElementById('length_max').value ) +
    "&beam_min=" + encodeURI( document.getElementById('beam_min').value ) +
    "&beam_max=" + encodeURI( document.getElementById('beam_max').value ) +
    "&draft_min=" + encodeURI( document.getElementById('draft_min').value ) +
    "&draft_max=" + encodeURI( document.getElementById('draft_max').value ) +
    "&year_oldest=" + encodeURI( document.getElementById('year_oldest').value ) +
    "&year_newest=" + encodeURI( document.getElementById('year_newest').value );
  makePOSTRequest('/static/boatsearch.php', poststr);
}


function createRequestObject() {
  var req;
  if(window.XMLHttpRequest){
    // Firefox, Safari, Opera...
    req = new XMLHttpRequest();
  } else if(window.ActiveXObject) {
    // Internet Explorer 5+
    req = new ActiveXObject("Microsoft.XMLHTTP");
  } else {
    // There is an error creating the object,
    // just as an old browser is being used.
    alert('There was a problem creating the XMLHttpRequest object');
  }
  return req;
}


// Make the XMLHttpRequest object
var http = createRequestObject();
var placeId = "";
var updateInfo = "";
var refreshTime = 0;


function sendRequest(act) {
  // Open PHP script for requests
  http.open('get', '/dynamic/ajax.php?act='+act);
  http.onreadystatechange = handleRes;
  http.send(null);
}


function handleRes() {
  if(http.readyState == 4 && http.status == 200){
    // Text returned FROM PHP script
    var response = http.responseText;
    if(response) {
      // UPDATE content
      document.getElementById(placeId).innerHTML = response;
      if(refreshTime>0) {
        setTimeout(liveUpdate,refreshTime);
      }
    }
  }
}


function liveUpdate() {
  sendRequest(updateInfo);
}


function updateNow(uinfo,uid,utime) {
  updateInfo = uinfo;
  placeId = uid;
  refreshTime = utime;
//    alert('XMLHttpRequest object called : '+updateInfo+' '+placeId+' '+refreshTime);
  sendRequest(updateInfo);
}


function makePOSTRequest(url, parameters) {
  http_request = false;
  if (window.XMLHttpRequest) { // Mozilla, Safari,...
     http_request = new XMLHttpRequest();
     if (http_request.overrideMimeType) {
      // set type accordingly to anticipated content type
        //http_request.overrideMimeType('text/xml');
        http_request.overrideMimeType('text/html');
     }
  } else if (window.ActiveXObject) { // IE
     try {
        http_request = new ActiveXObject("Msxml2.XMLHTTP");
     } catch (e) {
        try {
           http_request = new ActiveXObject("Microsoft.XMLHTTP");
        } catch (e) {}
     }
  }
  if (!http_request) {
     alert('Cannot create XMLHTTP instance');
     return false;
  }

  http_request.onreadystatechange = alertContents;
  http_request.open('POST', url, true);
  http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
  http_request.setRequestHeader("Content-length", parameters.length);
  http_request.setRequestHeader("Connection", "close");
  http_request.send(parameters);
}


function alertContents() {
  if (http_request.readyState == 4) {
     if (http_request.status == 200) {
        //alert(http_request.responseText);
        result = http_request.responseText;
        document.getElementById('searchform').innerHTML = result;
     } else {
        alert('There was a problem with the request.');
     }
  }
}