How to create thumbnail of dynamic content?

Hi, here is something that you can try.
First I defined a GridView control with bound fields like this:

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
    <Columns>
        <asp:BoundField DataField="FileName" />
        <asp:ImageField DataImageUrlField="FileThumbnailUrl">asp:ImageField>
    Columns>
asp:GridView>

And here is how I bind it with some sample data:

var table = new DataTable();
table.Columns.Add(new DataColumn("FileName", typeof(string)));
table.Columns.Add(new DataColumn("FileThumbnailUrl", typeof(string)));
 
foreach (var wordFile in Directory.GetFiles(Server.MapPath("~/Sample Files/"), "*.doc"))
{
    string thumbnailFile = wordFile.Replace(".doc", ".png");
 
    DocumentModel.Load(wordFile)
                    .Save(thumbnailFile,
                    new ImageSaveOptions(ImageSaveFormat.Png)
                    {
                        Width = 200,
                        Height = 250
                    });
 
    table.Rows.Add(Path.GetFileName(wordFile),
                    this.ResolveUrl(
                        Path.Combine("Sample Files", Path.GetFileName(thumbnailFile))));
}
 
this.GridView1.DataSource = table;
this.GridView1.DataBind();

And here is the result:

In short I have a "Sample Files" folder where my DOC files are located and I iterate through each of them and convert them to an image and store the image's URL to DataTable.
For reading the Word files in C# and then converting them to an image format I used this .NET component for Word files processing.
Note that this component can enable to manipulate (open, read and then convert) with DOC files in C# but also you can achive the same manipulation for DOCX files in C# as well.