这篇文章主要为大家展示了“HTML5如何实现上传文件显示进度”,内容简而易懂,条理清晰,希望能够帮助大家解决疑惑,下面让小编带领大家一起研究并学习一下“HTML5如何实现上传文件显示进度”这篇文章吧。
这里我们是结合Asp.net MVC做为服务端,您也可以是其它的服务端语言。让我们看面这个片断的HTML:
@using (Html.BeginForm("Upload", "Home", FormMethod.Post, new { enctype = "multipart/form-data" , id="form1"}))
{
<div class="row">
<label for="file">
Upload Image:</label>
<input type="file" name="fileToUpload" id="fileToUpload" multiple="multiple" onchange="fileSelected();" />
</div>
<div id="fileName">
</div>
<div id="fileSize">
</div>
<div id="fileType">
</div>
<div class="row">
<input type="button" onclick="uploadFile()" value="Upload Image" />
</div>
<div id="progressNumber">
</div>
}
相关的Javascript是这样的:
function fileSelected() {
var file = document.getElementById('fileToUpload').files[0];
if (file) {
var fileSize = 0;
if (file.size > 1024 * 1024)
fileSize = (Math.round(file.size * 100 / (1024 * 1024)) / 100).toString() + 'MB';
else
fileSize = (Math.round(file.size * 100 / 1024) / 100).toString() + 'KB';
document.getElementById('fileName').innerHTML = 'Name: ' + file.name;
document.getElementById('fileSize').innerHTML = 'Size: ' + fileSize;
document.getElementById('fileType').innerHTML = 'Type: ' + file.type;
}
}
function uploadFile() {
var fd = new FormData();
fd.append("fileToUpload", document.getElementById('fileToUpload').files[0]);
var xhr = new XMLHttpRequest();
xhr.upload.addEventListener("progress", uploadProgress, false);
xhr.addEventListener("load", uploadComplete, false);
xhr.addEventListener("error", uploadFailed, false);
xhr.addEventListener("abort", uploadCanceled, false);
xhr.open("POST", "Home/Upload");
xhr.send(fd);
}
function uploadProgress(evt) {
if (evt.lengthComputable) {
var percentComplete = Math.round(evt.loaded * 100 / evt.total);
document.getElementById('progressNumber').innerHTML = percentComplete.toString() + '%';
}
else {
document.getElementById('progressNumber').innerHTML = 'unable to compute';
}
}
function uploadComplete(evt) {
alert(evt.target.responseText);
}
function uploadFailed(evt) {
alert("There was an error attempting to upload the file.");
}
function uploadCanceled(evt) {
alert("The upload has been canceled by the user or the browser dropped the connection.");
}
上面是就原生的Javascript,在onchange事件执行fileSelected的function,在点击button执行了uploadFile的function,这里使用XMLHttpRequest实现ajax上传文件。 注意代码在Firefox 14 可以工作,IE 9目前不支持file api,可以参加这里。 服务端的代码很简单:
public class HomeController : Controller
{
public ActionResult Index()
{
return View();
}
/// <summary>
/// Uploads the specified files.
/// </summary>
/// <param name="fileToUpload">The files.</param>
/// <returns>ActionResult</returns>
[HttpPost]
public ActionResult Upload(HttpPostedFileBase[] fileToUpload)
{
foreach (HttpPostedFileBase file in fileToUpload)
{
string path = System.IO.Path.Combine(Server.MapPath("~/App_Data"), System.IO.Path.GetFileName(file.FileName));
file.SaveAs(path);
}
ViewBag.Message = "File(s) uploaded successfully";
return RedirectToAction("Index");
}
}
以上是“HTML5如何实现上传文件显示进度”这篇文章的所有内容,感谢各位的阅读!相信大家都有了一定的了解,希望分享的内容对大家有所帮助,如果还想学习更多知识,欢迎关注编程网行业资讯频道!