Restrict user to upload only PDF file using ASP.Net FileUpload

Hi phonghue,

Check this example. Now please take its reference and correct your code.

HTML

<div>
    <asp:FileUpload ID="FileUpload1" runat="server" accept="application/pdf" />
    <asp:Button ID="btnUpload" runat="server" Text="Upload" OnClick="Upload" />
    <hr />
    <asp:Label ID="lblMessage" ForeColor="Green" runat="server" />
</div>
<div>
    <asp:GridView ID="gvImages" runat="server" AutoGenerateColumns="false">
        <Columns>
            <asp:BoundField DataField="name" HeaderText="Image Id" />
        </Columns>
    </asp:GridView>
</div>

Namespaces

C#

using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.IO;

VB.Net

Imports System.Configuration
Imports System.Data
Imports System.Data.SqlClient
Imports System.Drawing
Imports System.IO

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        BindImageGrid();
    }
}

private void BindImageGrid()
{
    string connString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection conn = new SqlConnection(connString))
    {
        using (SqlDataAdapter sda = new SqlDataAdapter("SELECT * FROM tblFiles", conn))
        {
            DataTable dt = new DataTable();
            sda.Fill(dt);
            gvImages.DataSource = dt;
            gvImages.DataBind();
        }
    }
}

protected void Upload(object sender, EventArgs e)
{
    string filename = Path.GetFileName(FileUpload1.PostedFile.FileName);
    string extension = Path.GetExtension(filename);
    string contentType = FileUpload1.PostedFile.ContentType;
    // Check file extension.
    if (extension.ToLower() == ".pdf")
    {
        using (Stream fs = FileUpload1.PostedFile.InputStream)
        {
            using (BinaryReader br = new BinaryReader(fs))
            {
                byte[] bytes = br.ReadBytes(Convert.ToInt32(fs.Length));
                string connString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
                using (SqlConnection conn = new SqlConnection(connString))
                {
                    string query = "INSERT INTO tblFiles (Name, Contenttype, data) VALUES (@Name, @ContentType, @Data)";
                    using (SqlCommand cmd = new SqlCommand(query))
                    {
                        cmd.Connection = conn;
                        cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = filename;
                        cmd.Parameters.Add("@ContentType", SqlDbType.VarChar).Value = contentType;
                        cmd.Parameters.Add("@Data", SqlDbType.Binary).Value = bytes;
                        conn.Open();
                        cmd.ExecuteNonQuery();
                        conn.Close();
                    }
                }
            }
        }

        lblMessage.Text = "File uploaded successfully.";
        lblMessage.ForeColor = Color.Green;
        BindImageGrid();
    }
    else
    {
        lblMessage.Text = "Select only pdf file.";
        lblMessage.ForeColor = Color.Red;
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        BindImageGrid()
    End If
End Sub

Private Sub BindImageGrid()
    Dim connString As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using conn As SqlConnection = New SqlConnection(connString)
        Using sda As SqlDataAdapter = New SqlDataAdapter("SELECT * FROM tblFiles", conn)
            Dim dt As DataTable = New DataTable()
            sda.Fill(dt)
            gvImages.DataSource = dt
            gvImages.DataBind()
        End Using
    End Using
End Sub

Protected Sub Upload(ByVal sender As Object, ByVal e As EventArgs)
    Dim filename As String = Path.GetFileName(FileUpload1.PostedFile.FileName)
    Dim extension As String = Path.GetExtension(filename)
    Dim contentType As String = FileUpload1.PostedFile.ContentType
    ' Check file extension.
    If extension.ToLower() = ".pdf" Then
        Using fs As Stream = FileUpload1.PostedFile.InputStream
            Using br As BinaryReader = New BinaryReader(fs)
                Dim bytes As Byte() = br.ReadBytes(Convert.ToInt32(fs.Length))
                Dim connString As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString

                Using conn As SqlConnection = New SqlConnection(connString)
                    Dim query As String = "INSERT INTO tblFiles (Name, Contenttype, data) VALUES (@Name, @ContentType, @Data)"
                    Using cmd As SqlCommand = New SqlCommand(query)
                        cmd.Connection = conn
                        cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = filename
                        cmd.Parameters.Add("@ContentType", SqlDbType.VarChar).Value = contentType
                        cmd.Parameters.Add("@Data", SqlDbType.Binary).Value = bytes
                        conn.Open()
                        cmd.ExecuteNonQuery()
                        conn.Close()
                    End Using
                End Using
            End Using
        End Using
        lblMessage.Text = "File uploaded successfully."
        lblMessage.ForeColor = Color.Green
        BindImageGrid()
    Else
        lblMessage.Text = "Select only pdf file."
        lblMessage.ForeColor = Color.Red
    End If
End Sub