我正在使用HTML5构建拖放式Web应用程序,并将文件拖放到div上,当然要获取dataTransfer对象,这给了我FileList。
现在,我想删除一些文件,但是我不知道怎么办,或者甚至可能。
最好是我只想从FileList中删除它们;我没有用。但是,如果那不可能,我是否应该在与FileList交互的代码中编写检查代码?那看起来很麻烦。
我正在使用HTML5构建拖放式Web应用程序,并将文件拖放到div上,当然要获取dataTransfer对象,这给了我FileList。
现在,我想删除一些文件,但是我不知道怎么办,或者甚至可能。
最好是我只想从FileList中删除它们;我没有用。但是,如果那不可能,我是否应该在与FileList交互的代码中编写检查代码?那看起来很麻烦。
Answers:
如果只想删除几个选定的文件,则不能。您链接到的File API Working Draft包含注释:
该
HTMLInputElement
接口[HTML5]有一个只读FileList
属性,[...]
[重点煤矿]
阅读了一些HTML 5工作草案后,我遇到了Common input
element APIs。您似乎可以通过将对象的属性设置为空字符串来删除整个文件列表,例如:value
input
document.getElementById('multifile').value = "";
顺便说一句,使用Web应用程序中的文件一文也可能引起您的兴趣。
length
我认为只有 只读。我尝试删除带有拼接的项目,但在Chrome中失败。
该问题已被标记为已回答,但是我想分享一些信息,这些信息可能对使用FileList的其他人有所帮助。
将FileList视为数组会很方便,但是sort,shift,pop和slice之类的方法不起作用。正如其他人所建议的,您可以将FileList复制到数组。但是,没有使用循环,而是有一种简单的单行解决方案来处理此转换。
// fileDialog.files is a FileList
var fileBuffer=[];
// append the file list to an array
Array.prototype.push.apply( fileBuffer, fileDialog.files ); // <-- here
// And now you may manipulated the result as required
// shift an item off the array
var file = fileBuffer.shift(0,1); // <-- works as expected
console.info( file.name + ", " + file.size + ", " + file.type );
// sort files by size
fileBuffer.sort(function(a,b) {
return a.size > b.size ? 1 : a.size < b.size ? -1 : 0;
});
经过FF,Chrome和IE10 +的测试合格
Array.from(fileDialog.files)
更简单
fileDialog.files = fileBuffer
?
如果您以常绿浏览器(Chrome,Firefox,Edge,但也可以在Safari 9+中运行)为目标,或者您可以负担得起polyfill,则可以使用以下方式将FileList转换为数组Array.from()
:
let fileArray = Array.from(fileList);
这样就很容易File
像处理其他数组一样处理s数组。
fileArray
不了fileList
。
由于我们处于HTML5领域,因此这是我的解决方案。要点是,将文件推送到Array而不是将它们保留在FileList中,然后使用XHR2将文件推送到FormData对象。下面的例子。
Node.prototype.replaceWith = function(node)
{
this.parentNode.replaceChild(node, this);
};
if(window.File && window.FileList)
{
var topicForm = document.getElementById("yourForm");
topicForm.fileZone = document.getElementById("fileDropZoneElement");
topicForm.fileZone.files = new Array();
topicForm.fileZone.inputWindow = document.createElement("input");
topicForm.fileZone.inputWindow.setAttribute("type", "file");
topicForm.fileZone.inputWindow.setAttribute("multiple", "multiple");
topicForm.onsubmit = function(event)
{
var request = new XMLHttpRequest();
if(request.upload)
{
event.preventDefault();
topicForm.ajax.value = "true";
request.upload.onprogress = function(event)
{
var progress = event.loaded.toString() + " bytes transfered.";
if(event.lengthComputable)
progress = Math.round(event.loaded / event.total * 100).toString() + "%";
topicForm.fileZone.innerHTML = progress.toString();
};
request.onload = function(event)
{
response = JSON.parse(request.responseText);
// Handle the response here.
};
request.open(topicForm.method, topicForm.getAttribute("action"), true);
var data = new FormData(topicForm);
for(var i = 0, file; file = topicForm.fileZone.files[i]; i++)
data.append("file" + i.toString(), file);
request.send(data);
}
};
topicForm.fileZone.firstChild.replaceWith(document.createTextNode("Drop files or click here."));
var handleFiles = function(files)
{
for(var i = 0, file; file = files[i]; i++)
topicForm.fileZone.files.push(file);
};
topicForm.fileZone.ondrop = function(event)
{
event.stopPropagation();
event.preventDefault();
handleFiles(event.dataTransfer.files);
};
topicForm.fileZone.inputWindow.onchange = function(event)
{
handleFiles(topicForm.fileZone.inputWindow.files);
};
topicForm.fileZone.ondragover = function(event)
{
event.stopPropagation();
event.preventDefault();
};
topicForm.fileZone.onclick = function()
{
topicForm.fileZone.inputWindow.focus();
topicForm.fileZone.inputWindow.click();
};
}
else
topicForm.fileZone.firstChild.replaceWith(document.createTextNode("It's time to update your browser."));
我已经找到了非常快捷的解决方案。在许多流行的浏览器(Chrome,Firefox,Safari)中经过测试;
首先,您必须将FileList转换为数组
var newFileList = Array.from(event.target.files);
删除特定元素使用此
newFileList.splice(index,1);
event.target.files
未链接到输入,因此它不能只是局部变量改变什么..
这是临时的,但是我遇到了用这种方法解决的相同问题。就我而言,我是通过XMLHttp请求上传文件的,因此我能够通过formdata追加发布FileList克隆的数据。功能是您可以随意拖放或选择多个文件(再次选择文件不会重置克隆的FileList),从(克隆的)文件列表中删除所需的任何文件,以及通过xmlhttprequest进行提交留在那里。这就是我所做的。这是我的第一篇文章,因此代码有些混乱。抱歉。嗯,我不得不使用jQuery而不是Joomla脚本中的$。
// some global variables
var clon = {}; // will be my FileList clone
var removedkeys = 0; // removed keys counter for later processing the request
var NextId = 0; // counter to add entries to the clone and not replace existing ones
jQuery(document).ready(function(){
jQuery("#form input").change(function () {
// making the clone
var curFiles = this.files;
// temporary object clone before copying info to the clone
var temparr = jQuery.extend(true, {}, curFiles);
// delete unnecessary FileList keys that were cloned
delete temparr["length"];
delete temparr["item"];
if (Object.keys(clon).length === 0){
jQuery.extend(true, clon, temparr);
}else{
var keysArr = Object.keys(clon);
NextId = Math.max.apply(null, keysArr)+1; // FileList keys are numbers
if (NextId < curFiles.length){ // a bug I found and had to solve for not replacing my temparr keys...
NextId = curFiles.length;
}
for (var key in temparr) { // I have to rename new entries for not overwriting existing keys in clon
if (temparr.hasOwnProperty(key)) {
temparr[NextId] = temparr[key];
delete temparr[key];
// meter aca los cambios de id en los html tags con el nuevo NextId
NextId++;
}
}
jQuery.extend(true, clon, temparr); // copy new entries to clon
}
// modifying the html file list display
if (NextId === 0){
jQuery("#filelist").html("");
for(var i=0; i<curFiles.length; i++) {
var f = curFiles[i];
jQuery("#filelist").append("<p id=\"file"+i+"\" style=\'margin-bottom: 3px!important;\'>" + f.name + "<a style=\"float:right;cursor:pointer;\" onclick=\"BorrarFile("+i+")\">x</a></p>"); // the function BorrarFile will handle file deletion from the clone by file id
}
}else{
for(var i=0; i<curFiles.length; i++) {
var f = curFiles[i];
jQuery("#filelist").append("<p id=\"file"+(i+NextId-curFiles.length)+"\" style=\'margin-bottom: 3px!important;\'>" + f.name + "<a style=\"float:right;cursor:pointer;\" onclick=\"BorrarFile("+(i+NextId-curFiles.length)+")\">x</a></p>"); // yeap, i+NextId-curFiles.length actually gets it right
}
}
// update the total files count wherever you want
jQuery("#form p").text(Object.keys(clon).length + " file(s) selected");
});
});
function BorrarFile(id){ // handling file deletion from clone
jQuery("#file"+id).remove(); // remove the html filelist element
delete clon[id]; // delete the entry
removedkeys++; // add to removed keys counter
if (Object.keys(clon).length === 0){
jQuery("#form p").text(Object.keys(clon).length + " file(s) selected");
jQuery("#fileToUpload").val(""); // I had to reset the form file input for my form check function before submission. Else it would send even though my clone was empty
}else{
jQuery("#form p").text(Object.keys(clon).length + " file(s) selected");
}
}
// now my form check function
function check(){
if( document.getElementById("fileToUpload").files.length == 0 ){
alert("No file selected");
return false;
}else{
var _validFileExtensions = [".pdf", ".PDF"]; // I wanted pdf files
// retrieve input files
var arrInputs = clon;
// validating files
for (var i = 0; i < Object.keys(arrInputs).length+removedkeys; i++) {
if (typeof arrInputs[i]!="undefined"){
var oInput = arrInputs[i];
if (oInput.type == "application/pdf") {
var sFileName = oInput.name;
if (sFileName.length > 0) {
var blnValid = false;
for (var j = 0; j < _validFileExtensions.length; j++) {
var sCurExtension = _validFileExtensions[j];
if (sFileName.substr(sFileName.length - sCurExtension.length, sCurExtension.length).toLowerCase() == sCurExtension.toLowerCase()) {
blnValid = true;
break;
}
}
if (!blnValid) {
alert("Sorry, " + sFileName + " is invalid, allowed extensions are: " + _validFileExtensions.join(", "));
return false;
}
}
}else{
alert("Sorry, " + arrInputs[0].name + " is invalid, allowed extensions are: " + _validFileExtensions.join(" or "));
return false;
}
}
}
// proceed with the data appending and submission
// here some hidden input values i had previously set. Now retrieving them for submission. My form wasn't actually even a form...
var fecha = jQuery("#fecha").val();
var vendor = jQuery("#vendor").val();
var sku = jQuery("#sku").val();
// create the formdata object
var formData = new FormData();
formData.append("fecha", fecha);
formData.append("vendor", encodeURI(vendor));
formData.append("sku", sku);
// now appending the clone file data (finally!)
var fila = clon; // i just did this because I had already written the following using the "fila" object, so I copy my clone again
// the interesting part. As entries in my clone object aren't consecutive numbers I cannot iterate normally, so I came up with the following idea
for (i = 0; i < Object.keys(fila).length+removedkeys; i++) {
if(typeof fila[i]!="undefined"){
formData.append("fileToUpload[]", fila[i]); // VERY IMPORTANT the formdata key for the files HAS to be an array. It will be later retrieved as $_FILES['fileToUpload']['temp_name'][i]
}
}
jQuery("#submitbtn").fadeOut("slow"); // remove the upload btn so it can't be used again
jQuery("#drag").html(""); // clearing the output message element
// start the request
var xhttp = new XMLHttpRequest();
xhttp.addEventListener("progress", function(e) {
var done = e.position || e.loaded, total = e.totalSize || e.total;
}, false);
if ( xhttp.upload ) {
xhttp.upload.onprogress = function(e) {
var done = e.position || e.loaded, total = e.totalSize || e.total;
var percent = done / total;
jQuery("#drag").html(Math.round(percent * 100) + "%");
};
}
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var respuesta = this.responseText;
jQuery("#drag").html(respuesta);
}
};
xhttp.open("POST", "your_upload_handler.php", true);
xhttp.send(formData);
return true;
}
};
现在为此的html和样式。我是一个新手,但是所有这些实际上对我有用,花了我一段时间才弄清楚。
<div id="form" class="formpos">
<!-- Select the pdf to upload:-->
<input type="file" name="fileToUpload[]" id="fileToUpload" accept="application/pdf" multiple>
<div><p id="drag">Drop your files here or click to select them</p>
</div>
<button id="submitbtn" onclick="return check()" >Upload</button>
// these inputs are passed with different names on the formdata. Be aware of that
// I was echoing this, so that's why I use the single quote for php variables
<input type="hidden" id="fecha" name="fecha_copy" value="'.$fecha.'" />
<input type="hidden" id="vendor" name="vendorname" value="'.$vendor.'" />
<input type="hidden" id="sku" name="sku" value="'.$sku.'"" />
</div>
<h1 style="width: 500px!important;margin:20px auto 0px!important;font-size:24px!important;">File list:</h1>
<div id="filelist" style="width: 500px!important;margin:10px auto 0px!important;">Nothing selected yet</div>
样式。我必须标记其中一些!重要的是要覆盖Joomla的行为。
.formpos{
width: 500px;
height: 200px;
border: 4px dashed #999;
margin: 30px auto 100px;
}
.formpos p{
text-align: center!important;
padding: 80px 30px 0px;
color: #000;
}
.formpos div{
width: 100%!important;
height: 100%!important;
text-align: center!important;
margin-bottom: 30px!important;
}
.formpos input{
position: absolute!important;
margin: 0!important;
padding: 0!important;
width: 500px!important;
height: 200px!important;
outline: none!important;
opacity: 0!important;
}
.formpos button{
margin: 0;
color: #fff;
background: #16a085;
border: none;
width: 508px;
height: 35px;
margin-left: -4px;
border-radius: 4px;
transition: all .2s ease;
outline: none;
}
.formpos button:hover{
background: #149174;
color: #0C5645;
}
.formpos button:active{
border:0;
}
我希望这有帮助。
感谢@Nicholas Anderson简单明了,这是您应用的代码,并使用jquery在我的代码上工作。
HTML。
<input class="rangelog btn border-aero" id="file_fr" name="file_fr[]" multiple type="file" placeholder="{$labels_helpfiles_placeholder_file}">
<span style="cursor: pointer; cursor: hand;" onclick="cleanInputs($('#file_fr'))"><i class="fa fa-trash"></i> Empty chosen files</span>
JS代码
function cleanInputs(fileEle){
$(fileEle).val("");
var parEle = $(fileEle).parent();
var newEle = $(fileEle).clone()
$(fileEle).remove();
$(parEle).prepend(newEle);
}
在Vue js中:
self.$refs.inputFile.value = ''
您可能希望创建一个数组,并使用该数组代替只读文件列表。
var myReadWriteList = new Array();
// user selects files later...
// then as soon as convenient...
myReadWriteList = FileListReadOnly;
之后,请针对列表而不是内置列表进行上传。我不确定您正在使用的上下文,但我正在使用一个发现的jquery插件,而我要做的就是获取该插件的源代码,并使用<script>
标签。然后在源代码上方添加了我的数组,以便它可以用作全局变量,并且插件可以引用它。
然后,只需换掉参考文献即可。
我认为这将允许您再次添加拖放操作,如果内置列表是只读的,那么如何将拖放的文件放入列表中?
:))
FileList
对象分配给myReadWriteList
变量时,它会将其类型从更改Array
为FileList
,因此这不是解决方案。