In this article I will explain with an example, how to upload and save (insert) files to Database Table, retrieve (display) files and download the files from Database Table in ASP.Net MVC.
Files will be uploaded and then will be saved (inserted) to Database Table. The saved (inserted) files will be retrieved and displayed in HTML Grid (Table) consisting of a Link for downloading the file from database.
Database
This article makes use of a table named tblFiles whose schema is defined as follows.
![Upload Files, Save (Insert) to database, Retrieve (Display) and Download Files from database in ASP.Net MVC]()
Note: You can download the database table SQL by clicking the download link below.
Namespaces
You will need to import the following namespaces.
using System.IO;
using System.Configuration;
using System.Data.SqlClient;
Model
The Model class consists of following properties.
public class FileModel
{
public int Id { get; set; }
public string Name { get; set; }
public string ContentType { get; set; }
public byte[] Data { get; set; }
}
Controller
The Controller consists of following Action methods.
Action method for handling GET operation
Inside the Action method, the GetFiles method is called inside which the records from the tblFiles table are fetched using ExecuteReader method and stored into a Generic List collection of FileModel class object which is ultimately returned.
Finally, the Generic List collection of FileModel class object is returned to the View.
Action method for handling POST operation for uploading Files
This Action method gets called when a File is selected and the Upload Button is clicked which accepts the HttpPostedFileBase as parameter.
The uploaded file is converted to BYTE Array using ReadBytes method of BinaryReader class and is inserted into the database table along with File Name and Content Type..
After successful insertion of the File, the GetFiles method is called and the Generic List collection of FileModel class object is returned to the View.
Action method for handling POST operation for downloading Files
When the Download Link inside the HTML Table (Grid) is clicked, the Id of the particular file is sent to this Action method and using the File Id, the File’s binary data is fetched from the database.
Finally, the File is downloaded using the File function which accepts the Binary data, Content Type and Name of the file.
public class HomeController : Controller
{
// GET: Home
public ActionResult Index()
{
return View(GetFiles());
}
[HttpPost]
public ActionResult Index(HttpPostedFileBase postedFile)
{
byte[] bytes;
using (BinaryReader br = new BinaryReader(postedFile.InputStream))
{
bytes = br.ReadBytes(postedFile.ContentLength);
}
string sql = "INSERT INTO tblFiles VALUES (@Name, @ContentType, @Data)";
string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand(sql, con))
{
cmd.Parameters.AddWithValue("@Name", Path.GetFileName(postedFile.FileName));
cmd.Parameters.AddWithValue("@ContentType", postedFile.ContentType);
cmd.Parameters.AddWithValue("@Data", bytes);
con.Open();
cmd.ExecuteNonQuery();
con.Close();
}
}
return View(GetFiles());
}
[HttpPost]
public FileResult DownloadFile(int? fileId)
{
byte[] bytes;
string fileName, contentType;
string sql = "SELECT Name, Data, ContentType FROM tblFiles WHERE Id=@Id";
string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand(sql, con))
{
cmd.Parameters.AddWithValue("@Id", fileId);
con.Open();
using (SqlDataReader sdr = cmd.ExecuteReader())
{
sdr.Read();
bytes = (byte[])sdr["Data"];
contentType = sdr["ContentType"].ToString();
fileName = sdr["Name"].ToString();
}
con.Close();
}
}
return File(bytes, contentType, fileName);
}
private static List<FileModel> GetFiles()
{
List<FileModel> files = new List<FileModel>();
string sql = "SELECT Id, Name FROM tblFiles";
string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand(sql, con))
{
con.Open();
using (SqlDataReader sdr = cmd.ExecuteReader())
{
while (sdr.Read())
{
files.Add(new FileModel
{
Id = Convert.ToInt32(sdr["Id"]),
Name = sdr["Name"].ToString()
});
}
}
con.Close();
}
}
return files;
}
}
View
HTML Markup
Inside the View, in the very first line the FileModel class is declared as IEnumerable which specifies that it will be available as a Collection.
The View consists of two HTML Form which has been created using the Html.BeginForm method with the following parameters.
ActionName – Name of the Action.
ControllerName – Name of the Controller. In this case the name is Home.
FormMethod – It specifies the Form Method i.e. GET or POST. In this case it will be set to POST.
Inside the View, following script file is inherited.
1. jquery.min.js
Uploading the File
This Form has been specified with enctype=“multipart/form-data” attribute as it is necessary for File Upload operation.
The Form consists of an HTML FileUpload and a Submit Button.
When the Submit Button is clicked, the UploadFile Action method for handling POST operation will be called.
Form for Downloading the File
This Form consists of an HTML HiddenField and a Hidden Submit Button.
When any
Download Link inside the HTML Table (Grid) is clicked, then the
DownloadFile JavaScript function is called, which sets the
FileId into the HiddenField and calls the
click event of the
Submit Button which ultimately submits the Form.
When the Form is submitted, the DownloadFile Action method is called, which performs the File download operation.
Displaying the Files
For displaying the files, an HTML Table is used. A FOR EACH loop will be executed over the Model which will generate the HTML Table rows with the File records.
@model IEnumerable<Upload_File_Database_MVC.Models.FileModel>
@{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>Index</title>
</head>
<body>
@using (Html.BeginForm("Index", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
<input type="file" name="postedFile" />
<input type="submit" id="btnUpload" value="Upload" />
}
@using (Html.BeginForm("DownloadFile", "Home", FormMethod.Post))
{
<input type="hidden" id="hfFileId" name="FileId" />
<input type="submit" id="btnDownload" value="Download" style="display:none" />
}
<hr />
<table cellpadding="0" cellspacing="0">
<tr>
<th style="width:50px">File ID</th>
<th style="width:120px">File Name</th>
<th style="width:80px">Download</th>
</tr>
@if (Model.Count() > 0)
{
foreach (var file in Model)
{
<tr>
<td>@file.Id</td>
<td>@file.Name</td>
<td><a href="javascript:;" onclick="DownloadFile(@file.Id)">Download</a></td>
</tr>
}
}
else
{
<tr>
<td colspan="3"> </td>
</tr>
}
</table>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<script type="text/javascript">
function DownloadFile(fileId) {
$("#hfFileId").val(fileId);
$("#btnDownload")[0].click();
};
</script>
</body>
</html>
Screenshot
![ASP.Net MVC: Upload Files, Save (Insert) to database, Retrieve (Display) and Download Files from database]()
Downloads
