SelectPdf for .NET - Start Conversion from Javascript - C# / ASP.NET Sample

This sample shows how to manually start the html to pdf conversion of the SelectPdf Library for .NET using a Javascript call.

SelectPdf exposes a global Javascript variable called selectpdf in the page that is being converted. Using this variable you can check if the javascript code is executed inside the converter (check if typeof(selectpdf) == "object"). The converter version can also be checked using selectpdf.version.

The most important feature of the Javascript interface is the possibility to manually start the page conversion to pdf with a javascript call. To do that, you must:
1. Set converter.Options.StartupMode = StartupMode.Manual
2. Call selectpdf.start() from javascript

- If converter.Options.StartupMode is set to StartupMode.Manual and selectpdf.start() is not called from javascript, the conversion will timeout.
- If converter.Options.StartupMode is set to the default value StartupMode.Automatic, the conversion will start without waiting for any javascript calls.

Below it's the link to a test page that waits for 3 seconds after it loads and then calls the javascript conversion method. Converting it in StartupMode.Manual mode will display the time elapsed. Converting it in StartupMode.Automatic mode will not show that 3 seconds time interval.

Test page


Conversion start mode:


Sample Code C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using SelectPdf;

namespace SelectPdf.Samples
    public partial class convert_from_js : System.Web.UI.Page
        protected void Page_Load(object sender, EventArgs e)
            if (!IsPostBack)
                string url = Page.ResolveUrl("~/files/js-conversion.html");
                TxtUrl.Text = (new Uri(Request.Url, url)).AbsoluteUri;
                LnkTest.NavigateUrl = url;

        protected void BtnCreatePdf_Click(object sender, EventArgs e)
            // instantiate a html to pdf converter object
            HtmlToPdf converter = new HtmlToPdf();

            // set startup mode
            converter.Options.StartupMode = (HtmlToPdfStartupMode)Enum.Parse(
                typeof(HtmlToPdfStartupMode), DdlStartupMode.SelectedValue, true);

            // set timeout
            int timeout = 10;
                timeout = Convert.ToInt32(TxtTimeout.Text);
            catch { }
            converter.Options.MaxPageLoadTime = timeout;

            // create a new pdf document converting an url
            PdfDocument doc = converter.ConvertUrl(TxtUrl.Text);

            // save pdf document
            doc.Save(Response, false, "Sample.pdf");

            // close pdf document