FormData is not defined - Firefox 3.6.28 alternative
form-data, javascript, jquery
Solution
FormData is an XMLHttpRequest Level 2 interface that makes it easy to submit a form (including file uploads) using XHR / Ajax. As you've discovered, it's only available in Firefox from version 4 onwards. (The MDN documentation has a browser compatibility table.)
I suggest trying the jQuery Form Plugin. It supports an iframe fallback for uploading files in older browsers.
Problem
I have the great job of having to finish off a job originally given to a contractor but was never completed. Not a problem however I've now been told that the system must support Firefox 3.6! Not great but not something I would lose sleep over until now! The system has a Ajax function that uses the FormData object and then uploads a document (usually a PDF). I've ran this through Firefox 3.6 and I get the following "FormData is not defined" var formData = new FormData($('form')[0]); That's fine as I can see that this object isn't supported, I just need to use a different method or means of collection... I used this: ``` var formData = Components.classes["@mozilla.org/files/formdata;1"] .createInstance(Components.interfaces.nsIDOMFormData); ``` However this gave me the following error! Permission denied for http://10.29.100.23:8080 to get property XPCComponents.classes I was unsure why this was... is the path "`@mozilla.org/files/formdata;1`" incorrect? I did more research and was getting nowhere! So I then thought about serializing the form changed the following to... ``` var formData = {}; $.each($('form')[0].serializeArray(), function(_, kv) { if (formData.hasOwnProperty(kv.name)) { formData[kv.name] = $.makeArray(formData[kv.name]); formData[kv.name].push(kv.value); }else { formData[kv.name] = kv.value; } }); ``` although this didn#t error the Ajax function wasn't uploading (I presume it wasn't recognizing or finding the file or it was just collecting a string for the file value). Does anyone have any recommendations on an alternative for FormData in older browsers, especially Firefox 3.6 - that's the only old browser I have to support. ** update **** this is the content of the form on the HTML page ``` <form action="" method="post" enctype="multipart/form-data" name="uploadForm" id="uploadForm" target="#"> <label for="fileField">Rechnung hochladen</label> <input type="file" name="fileField" id="fileField"> <progress id="progressbar" class="progressbar_margin hidden"></progress> </form> ```