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<!DOCTYPE html>
<title>drag & drop - cancelling the dropped file upload</title>
<style>
body > div {
height: 200px;
width: 200px;
background-color: orange;
}
</style>
<script>
var fails = [];
window.onload = function() {
var orange = document.getElementsByTagName('div')[0];
orange.ondragover = orange.ondragenter = function(e) {
e.preventDefault();
e.dataTransfer.dropEffect = 'copy';
};
orange.ondrop = function(e) {
//if the browser simulates a drop, it must do so with an empty FileList
e.preventDefault();
if( !e.dataTransfer.files ) {
fails[fails.length] = 'No dataTransfer.files for '+e.type;
}
if( !window.FileList ) {
fails[fails.length] = 'No FileList interface object';
finish();
return;
}
if( !( e.dataTransfer.files instanceof FileList ) ) {
fails[fails.length] = 'dataTransfer.files is not a FileList';
}
if( e.dataTransfer.files.length ) {
fails[fails.length] = 'dataTransfer.files.length is '+e.dataTransfer.files.length+' instead of 0 for '+e.type;
}
if( e.dataTransfer.files[0] ) {
fails[fails.length] = 'dataTransfer.files[0] exists for drop';
finish();
}
};
};
function finish() {
document.getElementsByTagName('p')[0].innerHTML = fails.length ? ( 'FAIL: ' + fails.join('<br>') ) : 'PASS';
}
</script>
<div></div>
<p>Save <a href="../resources/pass.png">this image</a> to your desktop. Use your pointing device to drag the saved file from your desktop onto the orange box, and release it. <strong>A confirmation dialog must appear, allowing you to choose to cancel the upload</strong>. Refuse it. Pass if nothing happens, or if the browser simply displays the image.</p>
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