![](/img/trans.png)
[英]How to download files from a database, and get them as image in Asp.net core MVC?
[英]How to download multiple files in ASP.NET Core MVC
如何下載多個文件? 如果用戶發送單個文件,顯示,如果用戶發送多個文件,如何設置?
這是我的 controller 代碼:
public IActionResult DownloadFile(int id)
{
byte[] bytes;
string fileName, contentType;
var model = new List<Files>();
var getdocument = _documentdata.GetDocumentbyDocumentId(id);
if (getdocument != null)
{
fileName = getdocument.Name;
contentType = getdocument.FileType;
bytes = getdocument.DataFiles;
return File(bytes, contentType: "application/octet-stream", fileName);
}
return Ok("Can't find the image");
}
當我單擊上傳下載時,上傳是否正在存儲在數據庫 2 個表中?
獲取文檔單一ID
public Files GetDocumentbyDocumentId(int documentId)
{
var list = (from doc in _auc.Files
where doc.DocumentId == documentId
select doc).FirstOrDefault();
return list;
}
要下載多個文件,您可以創建一個 zip 文件並在其中添加多個文件。 請參考以下示例:
在此示例中,我將查詢 Products 表並獲取它們的圖像內容,然后使用 Zip 文件下載它們。
public IActionResult DownLoadAll()
{
var zipName = $"TestFiles-{DateTime.Now.ToString("yyyy_MM_dd-HH_mm_ss")}.zip";
using (MemoryStream ms = new MemoryStream())
{
//required: using System.IO.Compression;
using (var zip = new ZipArchive(ms, ZipArchiveMode.Create, true))
{
//QUery the Products table and get all image content
_dbcontext.Products.ToList().ForEach(file =>
{
var entry = zip.CreateEntry(file.ProImageName);
using (var fileStream = new MemoryStream(file.ProImageContent))
using (var entryStream = entry.Open())
{
fileStream.CopyTo(entryStream);
}
});
}
return File( ms.ToArray(), "application/zip", zipName);
}
}
索引頁面中的代碼:
<a asp-controller="Product" asp-action="DownLoadAll">DownLoad All Images</a>
產品 model:
public class Product
{
[Key]
public int ProId { get; set; }
public string ProName { get; set; }
public string ProImageName { get; set; }
public byte[] ProImageContent { get; set; } //Image content.
public string ProImageContentType { get; set; }
//you can add another properties
}
output如下:
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.