As everyone else here has stated: You cannot upload just any file automatically with JavaScript.
HOWEVER! If you have access to the information you want to send in your code (i.e., not C:\passwords.txt
), then you can upload it as a blob-type, and then treat it as a file.
What the server will end up seeing will be indistinguishable from someone actually setting the value of <input type="file" />
. The trick, ultimately, is to begin a new XMLHttpRequest()
with the server...
function uploadFile (data) {
// define data and connections
var blob = new Blob([JSON.stringify(data)]);
var url = URL.createObjectURL(blob);
var xhr = new XMLHttpRequest();
xhr.open('POST', 'myForm.php', true);
// define new form
var formData = new FormData();
formData.append('someUploadIdentifier', blob, 'someFileName.json');
// action after uploading happens
xhr.onload = function(e) {
console.log("File uploading completed!");
};
// do the uploading
console.log("File uploading started!");
xhr.send(formData);
}
// This data/text below is local to the JS script, so we are allowed to send it!
uploadFile({'hello!':'how are you?'});
So, what could you possibly use this for? I use it for uploading HTML5 canvas elements as jpg's. This saves the user the trouble of having to open a file
input
element, only to select the local, cached image that they just resized, modified, etc.. But it should work for any file type.