Remove (Set) space between IText7 Paragraphs (IBlockElement) in ASP.Net

Hi comunidadmexi...,

You need to use the IBlockElement class SetProperty Property.

Refer below example.

string filename;
string html;
string dest;
Paragraph contents;
protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[]
        {
            new DataColumn("sID"),
            new DataColumn("contents")
        });
        dt.Rows.Add(1, "<h3 style=color:#0000ff;><strong>Section 1</strong></h3>");
        dt.Rows.Add(2, "<h4><strong>- Alert</strong></h4>");
        filename = @"C:\Users\developer4\Desktop\Management_" + Guid.NewGuid() + ".pdf";
        PdfWriter writer = new PdfWriter(filename);
        PdfDocument pdf = new PdfDocument(writer);
        Document document = new Document(pdf);

        if (dt.Rows.Count > 0)
        {
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                List<IElement> lst = HtmlConverter.ConvertToElements(dt.Rows[i]["contents"].ToString()).ToList();
                for (int j = 0; j < lst.Count; j++)
                {
                    IBlockElement element = (IBlockElement)lst[j];
                    element.SetProperty(Property.LEADING, new Leading(Leading.MULTIPLIED, -1f));
                    document.Add(element);
                }
            }

            dest = filename.ToString();
        }
        else
        {
            Console.WriteLine("No rows found.");
        }
        document.Close();

        Response.Clear();
        Response.ContentType = "application/pdf";
        Response.AppendHeader("Content-Disposition", "attachment; filename=" + dest);
        Response.TransmitFile(dest);
        Response.End();
    }
}