尝试使用angularJS和c#webapi从服务器下载文件
本文关键字:服务器 下载 文件 c#webapi angularJS | 更新日期: 2023-09-27 18:32:59
将文件上传到服务器时,它运行良好;没有损坏的文件。但是当我下载文件时(除了纯 txt:s 它们会消失)它们越来越大,变得腐败。经过大量调查,我不知道可能出了什么问题。我只是在写文件作为响应的流并下载 Blob。
欢迎任何想法!
严重依赖此线程作为解决方案;使用 AngularJS 从 ASP.NET Web API 方法下载文件
当前代码如下;
网站简介:
[Route("GetFile")]
public HttpResponseMessage GetFile()
{
HttpResponseMessage result = null;
//Get file object here
try
{
IEnumerable<string> headerValues = Request.Headers.GetValues("fileID");
int key = Int32.Parse(headerValues.FirstOrDefault());
var fetchFile = db.FileRecords.Single(a => a.id == key);
var localFilePath = fetchFile.path + fetchFile.name;
if (!System.IO.File.Exists(localFilePath))
{
result = Request.CreateResponse(HttpStatusCode.Gone);
}
else
{// serve the file to the client
//I have used the x-filename header to send the filename. This is a custom header for convenience.
//You should set the content-type mime header for your response too, so the browser knows the data format.
var info = System.IO.File.GetAttributes(localFilePath);
result = Request.CreateResponse(HttpStatusCode.OK);
result.Content = new StreamContent(new FileStream(localFilePath, FileMode.Open, FileAccess.Read));
result.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
result.Content.Headers.Add("x-filename", fetchFile.name);
result.Content.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("attachment");
result.Content.Headers.ContentDisposition.FileName = fetchFile.name;
}
return result;
}
catch (Exception e)
{
return Request.CreateResponse(HttpStatusCode.BadRequest);
}
}
视图:
<button type="button" class="btn btn-default btn-sm" data-localize="DOWNLOAD" ng-click="downloadFiles(file)">
Download file
</button>
控制器:
/******** FILE DOWNLOAD **********/
$scope.downloadFiles = function (file) {
$http({
method: 'GET',
cache: false,
url: host + 'api/Files/GetFile',
headers: {
'Content-Type': 'application/json; charset=utf-8',
'fileID': file.id
}
}).success(function (data, status, headers) {
var octetStreamMime = 'application/octet-stream';
var success = false;
// Get the headers
headers = headers();
// Get the filename from the x-filename header or default to "download.bin"
var filename = headers['x-filename'] || 'download.bin';
// Determine the content type from the header or default to "application/octet-stream"
var contentType = headers['content-type'] || octetStreamMime;
try {
console.log(filename);
// Try using msSaveBlob if supported
console.log("Trying saveBlob method ...");
var blob = new Blob([data], { type: contentType });
if (navigator.msSaveBlob)
navigator.msSaveBlob(blob, filename);
else {
// Try using other saveBlob implementations, if available
var saveBlob = navigator.webkitSaveBlob || navigator.mozSaveBlob || navigator.saveBlob;
if (saveBlob === undefined) throw "Not supported";
saveBlob(blob, filename);
}
console.log("saveBlob succeeded");
success = true;
} catch (ex) {
console.log("saveBlob method failed with the following exception:");
console.log(ex);
}
if (!success) {
// Get the blob url creator
var urlCreator = window.URL || window.webkitURL || window.mozURL || window.msURL;
if (urlCreator) {
// Try to use a download link
var link = document.createElement('a');
if ('download' in link) {
// Try to simulate a click
try {
// Prepare a blob URL
console.log("Trying download link method with simulated click ...");
var blob = new Blob([data], { type: contentType });
var url = urlCreator.createObjectURL(blob);
link.setAttribute('href', url);
// Set the download attribute (Supported in Chrome 14+ / Firefox 20+)
link.setAttribute("download", filename);
// Simulate clicking the download link
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);
console.log("Download link method with simulated click succeeded");
success = true;
} catch (ex) {
console.log("Download link method with simulated click failed with the following exception:");
console.log(ex);
}
}
if (!success) {
// Fallback to window.location method
try {
// Prepare a blob URL
// Use application/octet-stream when using window.location to force download
console.log("Trying download link method with window.location ...");
var blob = new Blob([data], { type: octetStreamMime });
var url = urlCreator.createObjectURL(blob);
window.location = url;
console.log("Download link method with window.location succeeded");
success = true;
} catch (ex) {
console.log("Download link method with window.location failed with the following exception:");
console.log(ex);
}
}
}
}
if (!success) {
// Fallback to window.open method
console.log("No methods worked for saving the arraybuffer, using last resort window.open");
window.open(httpPath, '_blank', '');
}
/******************/
}).error(function (data, status) {
console.log("Request failed with status: " + status);
// Optionally write the error out to scope
//$scope.errorDetails = "Request failed with status: " + status;
});
}
添加了 arraybuffer 作为 GET 请求的响应类型,现在浏览器可以正确解释文件。
/******** FILE DOWNLOAD **********/
$scope.downloadFiles = function (file) {
$http({
method: 'GET',
cache: false,
url: host + 'api/Files/GetFile',
responseType:'arraybuffer',
headers: {
'Content-Type': 'application/json; charset=utf-8',
'fileID': file.id
}