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Uploading Files through AJAX, Javascript has no way of grabbing the files from the client machine and sending it to the server. If you have seen this then it has to be done another way because doing it via javascript just isn’t possible. In order to do it without fancy jquery libraries like uploadify ( which uses flash ) you would have to resort to an more old fashioned way.

There is a different way to do it by using a hidden iframe, when the upload form is submitted it send the files to the iframe instead of a new page. So you can use the iframe to do a ajax like upload.

Use the following code to achieve the ajax like upload.

(This does NOT include the php upload script itself,  its just the front end code)

<html>

<script language="Javascript">
function fileUpload(form, action_url, div_id) {
    // Create the iframe...
    var iframe = document.createElement("iframe");
    iframe.setAttribute("id", "upload_iframe");
    iframe.setAttribute("name", "upload_iframe");
    iframe.setAttribute("width", "0");
    iframe.setAttribute("height", "0");
    iframe.setAttribute("border", "0");
    iframe.setAttribute("style", "width: 0; height: 0; border: none;");

    // Add to document...
    form.parentNode.appendChild(iframe);
    window.frames['upload_iframe'].name = "upload_iframe";

    iframeId = document.getElementById("upload_iframe");

    // Add event...
    var eventHandler = function () {

            if (iframeId.detachEvent) iframeId.detachEvent("onload", eventHandler);
            else iframeId.removeEventListener("load", eventHandler, false);

            // Message from server...
            if (iframeId.contentDocument) {
                content = iframeId.contentDocument.body.innerHTML;
            } else if (iframeId.contentWindow) {
                content = iframeId.contentWindow.document.body.innerHTML;
            } else if (iframeId.document) {
                content = iframeId.document.body.innerHTML;
            }

            document.getElementById(div_id).innerHTML = content;

            // Del the iframe...
            setTimeout('iframeId.parentNode.removeChild(iframeId)', 250);
        }

    if (iframeId.addEventListener) iframeId.addEventListener("load", eventHandler, true);
    if (iframeId.attachEvent) iframeId.attachEvent("onload", eventHandler);

    // Set properties of form...
    form.setAttribute("target", "upload_iframe");
    form.setAttribute("action", action_url);
    form.setAttribute("method", "post");
    form.setAttribute("enctype", "multipart/form-data");
    form.setAttribute("encoding", "multipart/form-data");

    // Submit the form...
    form.submit();

    document.getElementById(div_id).innerHTML = "Uploading...";
}
</script>

<!-- index.php could be any script server-side for receive uploads. -->
<form>
<input type="file" name="datafile" /></br>
<input type="button" value="upload"
        onClick="fileUpload(this.form,'index.php','upload'); return false;" >
<div id="upload"></div>
</form>

</html>
Janes Oosthuizen

Author Janes Oosthuizen

Programmer and Tech Junky from Cape Town, South-Africa. I have been programming for more than 15 years in various languages including ( CSS, HTML, javascript, PHP, MySQL, Wordpress and many other ).

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