Open Power Point (ppt pptx) file as Slideshow in browser in ASP.Net

Hi Sumeet,

Refer below sample.

Install Spire.Presentation library

Use the following command.

Install-Package Spire.Presentation

HTML

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" EmptyDataText="No files uploaded">
    <Columns>
        <asp:BoundField DataField="Text" HeaderText="File Name" />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:LinkButton ID="lnkPreview" Text="Preview" CommandArgument='<%# Eval("Value") %>'
                    runat="server" OnClick="Preview"></asp:LinkButton>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>
<hr />
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<script type="text/javascript" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" />
<script type="text/javascript">
    $(function () {
        $('.carousel').carousel({
            interval: 1000
        });
        $('.item')[0].className = "item active";
    });
</script>
<div id="myCarousel" class="carousel slide" align="center" data-ride="carousel" data-pause="hover">
    <div class="carousel-inner" align="center" role="listbox">
        <asp:Repeater ID="rptImages" runat="server">
            <ItemTemplate>
                <div class="item">
                    <div class="carousel-content">
                        <asp:Image ID="Image1" runat="server" ImageUrl='<%# Eval("Data") %>' />
                    </div>
                </div>
            </ItemTemplate>
        </asp:Repeater>
        <a class="left carousel-control" href="#myCarousel" role="button" data-slide="prev">
            <span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
            <span class="sr-only">Previous</span>
        </a>
        <a class="right carousel-control" href="#myCarousel" role="button" data-slide="next">
            <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
            <span class="sr-only">Next</span>
        </a>
    </div>
</div>

Namespaces

C#

using System.IO;
using Spire.Presentation;

VB.Net

Imports System.IO
Imports Spire.Presentation

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        string[] filePaths = Directory.GetFiles(Server.MapPath("~/Files/"));
        List<ListItem> files = new List<ListItem>();
        foreach (string filePath in filePaths)
        {
            files.Add(new ListItem(Path.GetFileName(filePath), filePath));
        }
        GridView1.DataSource = files;
        GridView1.DataBind();
    }
}

protected void Preview(object sender, EventArgs e)
{
    string filePath = (sender as LinkButton).CommandArgument;
    this.CreateSlideShow(filePath);
}

private void CreateSlideShow(string filePath)
{
    //Create a Presentation instance.
    using (Presentation presentation = new Presentation())
    {
        //Load a PowerPoint document.
        presentation.LoadFromFile(filePath);
        List<SlideData> slideImages = new List<SlideData>();
        //Iterate through all slides in the PowerPoint document.
        foreach (ISlide slide in presentation.Slides)
        {
            //Save each slide as PNG image.
            System.Drawing.Image image = slide.SaveAsImage();
            byte[] bytes = (byte[])(new System.Drawing.ImageConverter()).ConvertTo(image, typeof(byte[]));
            slideImages.Add(new SlideData { Data = "data:image/jpg;base64," + Convert.ToBase64String(bytes) });
        }

        rptImages.DataSource = slideImages;
        rptImages.DataBind();
    }
}

public class SlideData
{
    public string Data { get; set; }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Dim filePaths As String() = Directory.GetFiles(Server.MapPath("~/Files/"))
        Dim files As List(Of ListItem) = New List(Of ListItem)()
        For Each filePath As String In filePaths
            files.Add(New ListItem(Path.GetFileName(filePath), filePath))
        Next

        GridView1.DataSource = files
        GridView1.DataBind()
    End If
End Sub

Protected Sub Preview(ByVal sender As Object, ByVal e As EventArgs)
    Dim filePath As String = (TryCast(sender, LinkButton)).CommandArgument
    Me.CreateSlideShow(filePath)
End Sub

Private Sub CreateSlideShow(ByVal filePath As String)
    'Create a Presentation instance.
    Using presentation As Presentation = New Presentation()
        'Load a PowerPoint document.
        presentation.LoadFromFile(filePath)
        Dim slideImages As List(Of SlideData) = New List(Of SlideData)()
        'Iterate through all slides in the PowerPoint document.
        For Each slide As ISlide In presentation.Slides
            'Save each slide as PNG image.
            Dim image As System.Drawing.Image = slide.SaveAsImage()
            Dim bytes As Byte() = CType((New System.Drawing.ImageConverter()).ConvertTo(image, GetType(Byte())), Byte())
            slideImages.Add(New SlideData With {
                .Data = "data:image/jpg;base64," & Convert.ToBase64String(bytes)
            })
        Next

        rptImages.DataSource = slideImages
        rptImages.DataBind()
    End Using
End Sub

Public Class SlideData
    Public Property Data As String
End Class

Screenshot