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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Sending forms with pure AJAX &ndash; MDN</title>
<script type="text/javascript">

"use strict";

/*\
|*|
|*|  :: XMLHttpRequest.prototype.sendAsBinary() Polyfill ::
|*|
|*|  https://developer.mozilla.org/en-US/docs/DOM/XMLHttpRequest#sendAsBinary()
\*/

if (!XMLHttpRequest.prototype.sendAsBinary) {
  XMLHttpRequest.prototype.sendAsBinary = function(sData) {
    var nBytes = sData.length, ui8Data = new Uint8Array(nBytes);
    for (var nIdx = 0; nIdx < nBytes; nIdx++) {
      ui8Data[nIdx] = sData.charCodeAt(nIdx) & 0xff;
    }
    /* send as ArrayBufferView...: */
    this.send(ui8Data);
    /* ...or as ArrayBuffer (legacy)...: this.send(ui8Data.buffer); */
  };
}

/*\
|*|
|*|  :: AJAX Form Submit Framework ::
|*|
|*|  https://developer.mozilla.org/en-US/docs/DOM/XMLHttpRequest/Using_XMLHttpRequest
|*|
|*|  This framework is released under the GNU Public License, version 3 or later.
|*|  http://www.gnu.org/licenses/gpl-3.0-standalone.html
|*|
|*|  Syntax:
|*|
|*|   AJAXSubmit(HTMLFormElement);
\*/

var AJAXSubmit = (function () {

  function ajaxSuccess () {
    /* console.log("AJAXSubmit - Success!"); */
    alert(this.responseText);
    /* you can get the serialized data through the "submittedData" custom property: */
    /* alert(JSON.stringify(this.submittedData)); */
  }

  function submitData (oData) {
    /* the AJAX request... */
    var oAjaxReq = new XMLHttpRequest();
    oAjaxReq.submittedData = oData;
    oAjaxReq.onload = ajaxSuccess;
    if (oData.technique === 0) {
      /* method is GET */
      oAjaxReq.open("get", oData.receiver.replace(/(?:\?.*)?$/, oData.segments.length > 0 ? "?" + oData.segments.join("&") : ""), true);
      oAjaxReq.send(null);
    } else {
      /* method is POST */
      oAjaxReq.open("post", oData.receiver, true);
      if (oData.technique === 3) {
        /* enctype is multipart/form-data */
        var sBoundary = "---------------------------" + Date.now().toString(16);
        oAjaxReq.setRequestHeader("Content-Type", "multipart\/form-data; boundary=" + sBoundary);
        oAjaxReq.sendAsBinary("--" + sBoundary + "\r\n" + oData.segments.join("--" + sBoundary + "\r\n") + "--" + sBoundary + "--\r\n");
      } else {
        /* enctype is application/x-www-form-urlencoded or text/plain */
        oAjaxReq.setRequestHeader("Content-Type", oData.contentType);
        oAjaxReq.send(oData.segments.join(oData.technique === 2 ? "\r\n" : "&"));
      }
    }
  }

  function processStatus (oData) {
    if (oData.status > 0) { return; }
    /* the form is now totally serialized! do something before sending it to the server... */
    /* doSomething(oData); */
    /* console.log("AJAXSubmit - The form is now serialized. Submitting..."); */
    submitData (oData);
  }

  function pushSegment (oFREvt) {
    this.owner.segments[this.segmentIdx] += oFREvt.target.result + "\r\n";
    this.owner.status--;
    processStatus(this.owner);
  }

  function plainEscape (sText) {
    /* how should I treat a text/plain form encoding? what characters are not allowed? this is what I suppose...: */
    /* "4\3\7 - Einstein said E=mc2" ----> "4\\3\\7\ -\ Einstein\ said\ E\=mc2" */
    return sText.replace(/[\s\=\\]/g, "\\$&");
  }

  function SubmitRequest (oTarget) {
    var nFile, sFieldType, oField, oSegmReq, oFile, bIsPost = oTarget.method.toLowerCase() === "post";
    /* console.log("AJAXSubmit - Serializing form..."); */
    this.contentType = bIsPost && oTarget.enctype ? oTarget.enctype : "application\/x-www-form-urlencoded";
    this.technique = bIsPost ? this.contentType === "multipart\/form-data" ? 3 : this.contentType === "text\/plain" ? 2 : 1 : 0;
    this.receiver = oTarget.action;
    this.status = 0;
    this.segments = [];
    var fFilter = this.technique === 2 ? plainEscape : escape;
    for (var nItem = 0; nItem < oTarget.elements.length; nItem++) {
      oField = oTarget.elements[nItem];
      if (!oField.hasAttribute("name")) { continue; }
      sFieldType = oField.nodeName.toUpperCase() === "INPUT" ? oField.getAttribute("type").toUpperCase() : "TEXT";
      if (sFieldType === "FILE" && oField.files.length > 0) {
        if (this.technique === 3) {
          /* enctype is multipart/form-data */
          for (nFile = 0; nFile < oField.files.length; nFile++) {
            oFile = oField.files[nFile];
            oSegmReq = new FileReader();
            /* (custom properties:) */
            oSegmReq.segmentIdx = this.segments.length;
            oSegmReq.owner = this;
            /* (end of custom properties) */
            oSegmReq.onload = pushSegment;
            this.segments.push("Content-Disposition: form-data; name=\"" + oField.name + "\"; filename=\""+ oFile.name + "\"\r\nContent-Type: " + oFile.type + "\r\n\r\n");
            this.status++;
            oSegmReq.readAsBinaryString(oFile);
          }
        } else {
          /* enctype is application/x-www-form-urlencoded or text/plain or method is GET: files will not be sent! */
          for (nFile = 0; nFile < oField.files.length; this.segments.push(fFilter(oField.name) + "=" + fFilter(oField.files[nFile++].name)));
        }
      } else if ((sFieldType !== "RADIO" && sFieldType !== "CHECKBOX") || oField.checked) {
        /* field type is not FILE or is FILE but is empty */
        this.segments.push(
          this.technique === 3 ? /* enctype is multipart/form-data */
            "Content-Disposition: form-data; name=\"" + oField.name + "\"\r\n\r\n" + oField.value + "\r\n"
          : /* enctype is application/x-www-form-urlencoded or text/plain or method is GET */
            fFilter(oField.name) + "=" + fFilter(oField.value)
        );
      }
    }
    processStatus(this);
  }

  return function (oFormElement) {
    if (!oFormElement.action) { return; }
    new SubmitRequest(oFormElement);
  };

})();

</script>
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<h1>Sending forms with pure AJAX</h1>

<h2>Using the GET method</h2>

<form action="register.php" method="get" onsubmit="AJAXSubmit(this); return false;">
  <fieldset>
    <legend>Registration example</legend>
    <p>
      First name: <input type="text" name="firstname" /><br />
      Last name: <input type="text" name="lastname" />
    </p>
    <p>
      <input type="submit" value="Submit" />
    </p>
  </fieldset>
</form>

<h2>Using the POST method</h2>
<h3>Enctype: application/x-www-form-urlencoded (default)</h3>

<form action="register.php" method="post" onsubmit="AJAXSubmit(this); return false;">
  <fieldset>
    <legend>Registration example</legend>
    <p>
      First name: <input type="text" name="firstname" /><br />
      Last name: <input type="text" name="lastname" />
    </p>
    <p>
      <input type="submit" value="Submit" />
    </p>
  </fieldset>
</form>

<h3>Enctype: text/plain</h3>

<form action="register.php" method="post" enctype="text/plain" onsubmit="AJAXSubmit(this); return false;">
  <fieldset>
    <legend>Registration example</legend>
    <p>
      Your name: <input type="text" name="user" />
    </p>
    <p>
      Your message:<br />
      <textarea name="message" cols="40" rows="8"></textarea>
    </p>
    <p>
      <input type="submit" value="Submit" />
    </p>
  </fieldset>
</form>

<h3>Enctype: multipart/form-data</h3>

<form action="register.php" method="post" enctype="multipart/form-data" onsubmit="AJAXSubmit(this); return false;">
  <fieldset>
    <legend>Upload example</legend>
    <p>
      First name: <input type="text" name="firstname" /><br />
      Last name: <input type="text" name="lastname" /><br />
      Sex:
      <input id="sex_male" type="radio" name="sex" value="male" /> <label for="sex_male">Male</label>
      <input id="sex_female" type="radio" name="sex" value="female" /> <label for="sex_female">Female</label><br />
      Password: <input type="password" name="secret" /><br />
      What do you prefer:
      <select name="image_type">
        <option>Books</option>
        <option>Cinema</option>
        <option>TV</option>
      </select>
    </p>
    <p>
      Post your photos:
      <input type="file" multiple name="photos[]">
    </p>
    <p>
      <input id="vehicle_bike" type="checkbox" name="vehicle[]" value="Bike" /> <label for="vehicle_bike">I have a bike</label><br />
      <input id="vehicle_car" type="checkbox" name="vehicle[]" value="Car" /> <label for="vehicle_car">I have a car</label>
    </p>
    <p>
      Describe yourself:<br />
      <textarea name="description" cols="50" rows="8"></textarea>
    </p>
    <p>
      <input type="submit" value="Submit" />
    </p>
  </fieldset>
</form>

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