我有这个问题。 在合成中，我有一个下载按钮，单击时，执行这样一个Ajax请求：使用Ajax请求下载文件Extjs4
Ext.Ajax.request({
url: 'DownloadServlet',
method: 'GET',
});
该请求由一个servlet读取默认的文件进行处理。 该文件的读取是成功的，事实上，在萤火虫中，GET的状态是“200”。
问题是前端（extjs）似乎无法管理下载文件。我期望浏览器显示经典的更多窗口来下载文件。
什么可能呢？谢谢
您无法使用AJAX调用下载文件。基本上有两种解决方案：坚固而简单。
简单：只需使用window.popup或document.location.href来重定向您的文件存储的URL，您将获得正常的浏览器下载方法。硬件：你可以通过AJAX调用获得二进制或base64编码的文件内容，并创建一个带有base64编码href的下载链接。在Chrome中，它将如下所示：
<a href="base64,mime-type,...encoded trash..." download="download">
对于其他浏览器有一些解决方案，但目前它仅适用于Chrome。对于其他浏览器，我使用的代码那样：
var showSave;
// Feature test: Does this browser support the download attribute on anchor tags? (currently only Chrome)
var DownloadAttributeSupport = 'download' in document.createElement('a');
// Use any available BlobBuilder/URL implementation:
var BlobBuilder = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder || window.MSBlobBuilder;
var URL = window.URL || window.webkitURL || window.mozURL || window.msURL;
// IE 10 has a handy navigator.msSaveBlob method. Maybe other browsers will emulate that interface?
// See: http://msdn.microsoft.com/en-us/library/windows/apps/hh441122.aspx
navigator.saveBlob = navigator.saveBlob || navigator.msSaveBlob || navigator.mozSaveBlob || navigator.webkitSaveBlob;
// Anyway, HMTL5 defines a very similar but more powerful window.saveAs function:
// http://www.w3.org/TR/file-writer-api/#the-filesaver-interface
window.saveAs = window.saveAs || window.webkitSaveAs || window.mozSaveAs || window.msSaveAs;
// However, this is not supported by any browser yet. But there is a compatibility library that
// adds this function to browsers that support Blobs (except Internet Exlorer):
// http://eligrey.com/blog/post/saving-generated-files-on-the-client-side
// https://github.com/eligrey/FileSaver.js
// mime types that (potentially) don't trigger a download when opened in a browser:
var BrowserSupportedMimeTypes = {
"image/jpeg": true,
"image/png": true,
"image/gif": true,
"image/svg+xml": true,
"image/bmp": true,
"image/x-windows-bmp": true,
"image/webp": true,
"audio/wav": true,
"audio/mpeg": true,
"audio/webm": true,
"audio/ogg": true,
"video/mpeg": true,
"video/webm": true,
"video/ogg": true,
"text/plain": true,
"text/html": true,
"text/xml": true,
"application/xhtml+xml": true,
"application/json": true
};
// Blobs and saveAs (or saveBlob) :
if (BlobBuilder && (window.saveAs || navigator.saveBlob)) {
// Currently only IE 10 supports this, but I hope other browsers will also implement the saveAs/saveBlob method eventually.
showSave = function (data, name, mimeType) {
var builder = new BlobBuilder();
builder.append(data);
var blob = builder.getBlob(mimetype||"application/octet-stream");
if (!name) name = "Download.bin";
// I don't assign saveAs to navigator.saveBlob (or the other way around)
// because I cannot know at this point whether future implementations
// require these methods to be called with 'this' assigned to window (or
// naviagator) in order to work. E.g. console.log won't work when not called
// with this === console.
if (window.saveAs) {
window.saveAs(blob, name);
}
else {
navigator.saveBlob(blob, name);
}
};
}
else if (window.Blob && URL && window.atob) {
// atob to base64_decode the data-URI
showSave = function (data, name, mimetype) {
var image_data = atob(data);
// Use typed arrays to convert the binary data to a Blob
var arraybuffer = new ArrayBuffer(image_data.length);
var view = new Uint8Array(arraybuffer);
for (var i=0; i<image_data.length; i++) {
view[i] = image_data.charCodeAt(i) & 0xff;
}
var blob = new Blob([arraybuffer], {type: 'application/octet-stream'});
// Use the URL object to create a temporary URL
var url = URL.createObjectURL(blob);
//window.open(url, '_blank', '');
document.location.href = url
}
}
// Blobs and object URLs:
else if (BlobBuilder && URL) {
// Currently WebKit and Gecko support BlobBuilder and object URLs.
showSave = function (data, name, mimetype) {
var blob, url, builder = new BlobBuilder();
builder.append(data);
if (!mimetype) mimetype = "application/octet-stream";
if (DownloadAttributeSupport) {
blob = builder.getBlob(mimetype);
url = URL.createObjectURL(blob);
// Currently only Chrome (since 14-dot-something) supports the download attribute for anchor elements.
var link = document.createElement("a");
link.setAttribute("href",url);
link.setAttribute("download",name||"Download.bin");
// Now I need to simulate a click on the link.
// IE 10 has the better msSaveBlob method and older IE versions do not support the BlobBuilder interface
// and object URLs, so we don't need the MS way to build an event object here.
var event = document.createEvent('MouseEvents');
event.initMouseEvent('click', true, true, window, 1, 0, 0, 0, 0, false, false, false, false, 0, null);
link.dispatchEvent(event);
}
else {
// In other browsers I open a new window with the object URL.
// In order to trigger a download I have to use the generic binary data mime type
// "application/octet-stream" for mime types that browsers would display otherwise.
// Of course the browser won't show a nice file name here.
if (BrowserSupportedMimeTypes[mimetype.split(";")[0]] === true) {
mimetype = "application/octet-stream";
}
blob = builder.getBlob(mimetype);
url = URL.createObjectURL(blob);
//window.open(url, '_blank', '');
document.location.href = url
}
// The timeout is probably not necessary, but just in case that some browser handle the click/window.open
// asynchronously I don't revoke the object URL immediately.
setTimeout(function() {
URL.revokeObjectURL(url);
}, 250);
// Using the filesystem API (http://www.w3.org/TR/file-system-api/) you could do something very similar.
// However, I think this is only supported by Chrome right now and it is much more complicated than this
// solution. And chrome supports the download attribute anyway.
};
}
// data:-URLs:
else if (!/\bMSIE\b/.test(navigator.userAgent)) {
// IE does not support URLs longer than 2048 characters (actually bytes), so it is useless for data:-URLs.
// Also it seems not to support window.open in combination with data:-URLs at all.
showSave = function (data, name, mimetype) {
if (!mimetype) mimetype = "application/octet-stream";
// Again I need to filter the mime type so a download is forced.
if (BrowserSupportedMimeTypes[mimetype.split(";")[0]] === true) {
mimetype = "application/octet-stream";
}
// Note that encodeURIComponent produces UTF-8 encoded text. The mime type should contain
// the charset=UTF-8 parameter. In case you don't want the data to be encoded as UTF-8
// you could use escape(data) instead.
window.open("data:"+mimetype+";base64,"+data, '_blank', '');
};
}
// Internet Explorer before version 10 does not support any of the methods above.
// If it is text data you could show it in an textarea and tell the user to copy it into a text file.
更新时间： 如果你确定使用闪光灯，这里是对于非Chrome浏览器，备用解决方案： https://github.com/dcneiner/Downloadify
试试这个
downloadWhatever : function() {
Ext.core.DomHelper.append(document.body, {
tag : 'iframe',
id : 'downloadIframe',
frameBorder : 0,
width : 0,
height : 0,
css : 'display:none;visibility:hidden;height:0px;',
src : '/your/restful/url/'
});
},
服务器端弹簧（如果你不知道）
@RequestMapping(value = "/url", method = RequestMethod.GET)
public void download(HttpServletRequest request,
HttpServletResponse response) throws ServletRequestBindingException, IOException {
String tempFile = .. get your file
File file = new File(tempFile);
// in case you have zipped it ...
// else set the correct ContentType
response.setContentType("application/zip");
response.setContentLength((int) file.length());
response.setHeader("fileName", file.getName());
response.setHeader("Content-Disposition", "attachment; filename="+ file.getName());
InputStream in = new FileInputStream(file);
OutputStream out = response.getOutputStream();
byte[] buffer = new byte[1024];
int read = 0;
while ((read = in.read(buffer, 0, buffer.length)) != -1) {
out.write(buffer, 0, read);
}
in.close();
out.flush();
out.close();
}