In this article I will explain with an example, how to upload files, save (insert) to database table, retrieve (display) files from database table and download the files from database table in ASP.Net MVC Razor.
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;
using System.Collections.Generic;
Model
The following Model class consists of the following properties needed for inserting and populating the records of the Files from database.
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 three Action methods.
Action method for handling GET operation
Inside this Action method, the GetFiles method is called.
Inside the GetFiles method, the records from the tblFiles table are fetched using DataReader and generic list of FileModel class objects is populated.
Finally, the generic list of FileModel class objects 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, and it gets the uploaded file in the HttpPostedFileBase parameter.
The uploaded file is converted to an Array of Bytes using BinaryReader class and finally is inserted into the database table.
After successful insert of the File, the GetFiles method is called and the generic list of FileModel class objects 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, then 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.
Note: The following Action method performs File Download and hence the return type is set to FileResult.
Finally, the File is downloaded using the File function.
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 constr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
string query = "INSERT INTO tblFiles VALUES (@Name, @ContentType, @Data)";
using (SqlCommand cmd = new SqlCommand(query))
{
cmd.Connection = 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 constr = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = "SELECT Name, Data, ContentType FROM tblFiles WHERE Id=@Id";
cmd.Parameters.AddWithValue("@Id", fileId);
cmd.Connection = con;
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 constr = ConfigurationManager.ConnectionStrings["Constring"].ConnectionString;
using (SqlConnection con = new SqlConnection(constr))
{
using (SqlCommand cmd = new SqlCommand("SELECT Id, Name FROM tblFiles"))
{
cmd.Connection = 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
Now you will need to Right Click inside the Controller class and click on the Add View option in order to create a View for the Controller.
The Name of the View is set to Index, the Template option is set to Empty, the Model class is set to FileModel.
![Upload Files, Save (Insert) to database, Retrieve (Display) and Download Files from database in ASP.Net MVC]()
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 Forms:-
Form for Uploading the File
This Form consists of an HTML FileUpload and a Submit Button.
When the Submit Button is clicked, the Index 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 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 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="~/Scripts/jquery-1.10.2.min.js"></script>
<script type="text/javascript">
function DownloadFile(fileId) {
$("#hfFileId").val(fileId);
$("#btnDownload")[0].click();
};
</script>
</body>
</html>
Screenshot
![Upload Files, Save (Insert) to database, Retrieve (Display) and Download Files from database in ASP.Net MVC]()
Downloads
