ABCpdf .NET PDF Component Documentation - XHtmlOptions UseScript Property. Whether to enable JavaScript and VBScript.

UseScript Property

Type	Default Value	Read Only	Description
[C#] `bool` [Visual Basic] `Boolean`	true	No	Whether to enable JavaScript and VBScript.

Notes

This property determines whether JavaScript and VBScript are enabled.

By default client-side script such as JavaScript is enabled when rendering HTML documents. You may wish to change this default setting for performance or security reasons.

The ABCChrome engine relies on JavaScript for HTML analysis. If you disable it the HtmlOptions.Media, HtmlOptions.AddForms, HtmlOptions.AddTags and HtmlOptions.OnLoadScript will cease to operate. In addition the HtmlOptions.BrowserWidth zero setting, which allows the page autosize behavior, will default to the HtmlOptions.InitialWidth setting.

If you have a server edition of Windows (e.g. Windows Server 2008) and are using the MSHTML engine, you may need to also disable Enhanced Security Configuration for user running the program/application pool to allow JavaScript execution.

Script-Accessible Functions and Properties. These are functions and properties that script inside HTML can access. The function signatures shown are in C#-like syntax. You'll need to pass in the correct number of arguments.

bool ABCpdf_RenderWait();

Private Function ABCpdf_RenderWait() As Boolean

MSHTML only

window.external.ABCpdf_RenderWait – Delays ABCpdf's rendering of the HTML page.

Syntax

Params

Name	Description
return	True if ABCpdf waits (i.e. the function succeeds), otherwise false.

Notes

When this function is called before the page load is considered complete, the page load is not considered complete until ABCpdf_RenderComplete is called. This function returns false if ABCpdf_RenderComplete has been called. This is useful if the page relies on timeout/asynchronous events (AJAX).

bool ABCpdf_RenderComplete();
bool ABCpdf_RenderComplete(bool force);

Private Function ABCpdf_RenderComplete() As Boolean
Private Function ABCpdf_RenderComplete(ByVal force As Boolean) As Boolean

MSHTML only window.external.ABCpdf_RenderComplete – Resumes ABCpdf's rendering of the HTML page.

Syntax

Params

Name	Description
force	Whether ABCpdf ignores normal indications of page load completion. The default value is false.
return	True if ABCpdf resumes rendering as requested (i.e. the function succeeds), otherwise false.

Notes This function can be called whether ABCpdf_RenderWait has/has not been called. If force is false, ABCpdf resumes normal rendering. If force is true, ABCpdf starts rendering immediately, ignoring all other indications of page load completion. This function returns false if force is false and the function has been previously called with force true. This is useful if the page relies on timeout/asynchronous events (AJAX).

Examples

Doc doc = new Doc();
doc.HtmlOptions.Engine = EngineType.MSHtml;
doc.HtmlOptions.UseScript = true;

// Render after 3 seconds
doc.HtmlOptions.OnLoadScript = "(function(){"
  + " window.external.ABCpdf_RenderWait();"
  + " setTimeout(function(){ window.external.ABCpdf_RenderComplete(); }, 3000);"
  + "})();";

doc.AddImageUrl("http://www.websupergoo.com");
doc.Save(Server.MapPath("wsg.pdf"));

Dim theDoc As Doc = New Doc()
theDoc.HtmlOptions.Engine = EngineType.MSHtml
theDoc.HtmlOptions.UseScript = True

' Render after 3 seconds
theDoc.HtmlOptions.OnLoadScript = "(function(){" _
  & " window.external.ABCpdf_RenderWait();" _
  & " setTimeout(function(){ window.external.ABCpdf_RenderComplete(); }, 3000);" _
  & "})();"

theDoc.AddImageUrl("http://www.websupergoo.com")
theDoc.Save(Server.MapPath("wsg.pdf"))

bool ABCpdf_go;

Dim ABCpdf_go As Boolean

Gecko only window.ABCpdf_go – Specifies whether ABCpdf proceeds to render the HTML page.

Syntax

Params

Value	Description
undefined (initial value), true	ABCpdf proceeds to render the HTML page.
false	ABCpdf waits.

Notes UseScript has to be true and OnLoadScript has to be non-empty for this property to be effectual. ABCpdf will wait for this property to be either undefined or true before rendering the HTML page. The whole HTML rendering operation is still subject to the Timeout property's value. Usually, this property is set to false in OnLoadScript and is also set to true in an event listener added in OnLoadScript. If assignments to this property are provided in both OnLoadScript and the script in the web page, please refer to the notes in OnLoadScript for the order of execution.

Examples

Doc doc = new Doc();
doc.HtmlOptions.Engine = EngineType.Gecko;
doc.HtmlOptions.UseScript = true;

// Render after 3 seconds
doc.HtmlOptions.OnLoadScript = "(function(){"
  + " window.ABCpdf_go = false;"
  + " setTimeout(function(){ window.ABCpdf_go = true; }, 3000);"
  + "})();";

doc.AddImageUrl("http://www.websupergoo.com");
doc.Save(Server.MapPath("wsg.pdf"));

Dim theDoc As Doc = New Doc()
theDoc.HtmlOptions.Engine = EngineType.Gecko
theDoc.HtmlOptions.UseScript = True

' Render after 3 seconds
theDoc.HtmlOptions.OnLoadScript = "(function(){" _
  & " window.ABCpdf_go = false;" _
  & " setTimeout(function(){ window.ABCpdf_go = true; }, 3000);" _
  & "})();"

theDoc.AddImageUrl("http://www.websupergoo.com")
theDoc.Save(Server.MapPath("wsg.pdf"))

ABCChrome only ABCChromeExt.Render() – Triggers immediate conversion of the HTML page.

Syntax

void ABCChromeExt.Render();

Private Sub Render()

Params

Value	Description
n/a	n/a

Notes

Calling the method ABCChromeExt.Render() in any JavaScript executed within an HTML page will force the immediate rendering of the page to PDF without delay.

This option cannot be used in HtmlOptions.OnLoadScript - no error will occur but processing will not be curtailed.

You will need to set a sensible value for HtmlOptions.RenderDelay to allow processing to continue past the OnLoad event.

Example

The following example shows one method of crawling and transferring an entire site to PDF. Here, we use JavaScript to determine the links present on the page. However, you could equally well use the HtmlCallback to do the same thing.

using var doc = new Doc();
string uri = "https://photojournal.jpl.nasa.gov/gallery/snt";
// Set HTML options
doc.HtmlOptions.AddLinks = true;
doc.HtmlOptions.UseScript = true;
doc.HtmlOptions.PageCacheEnabled = false;
// JavaScript is used to extract all links from the page
doc.HtmlOptions.OnLoadScript = "var hrefCollection = document.all ? document.all.tags(\"a\") : document.getElementsByTagName(\"a\");" +
  "var allLinks = \"\";" +
  "for(i = 0; i < hrefCollection.length; ++i) {" +
  "if (i > 0)" +
  "  allLinks += \",\";" +
  "allLinks += hrefCollection.item(i).href;" +
  "};" +
  "document.documentElement.abcpdf = allLinks;";
// Array of links - start with base URL
var links = new ArrayList();
links.Add(uri);
for (int i = 0; i < links.Count; i++) {
  // Stop if we render more than 20 pages
  if (doc.PageCount > 20)
    break;
  // Add page
  doc.Page = doc.AddPage();
  int id = doc.AddImageUrl(links[i] as string);
  // Links from the rendered page
  string allLinks = doc.HtmlOptions.GetScriptReturn(id);
  string[] newLinks = allLinks.Split(new char[] { ',' });
  foreach (string link in newLinks) {
    // Check to see if we allready rendered this page
    if (links.BinarySearch(link) < 0) {
      // Skip links inside the page
      int pos = link.IndexOf("#");
      if (!(pos > 0 && links.BinarySearch(link.Substring(0, pos)) >= 0)) {
        if (link.StartsWith(uri)) {
          links.Add(link);
        }
      }
    }
  }
  // Add other pages
  while (true) {
    doc.FrameRect();
    if (!doc.Chainable(id))
      break;
    doc.Page = doc.AddPage();
    id = doc.AddImageToChain(id);
  }
}
// Link pages together
doc.HtmlOptions.LinkPages();
// Flatten all pages
for (int i = 1; i <= doc.PageCount; i++) {
  doc.PageNumber = i;
  doc.Flatten();
}
// Save the document
doc.Save(Server.MapPath("HtmlOptionsJavaScript.pdf"));

Using doc As New Doc()
  Dim theURL As String = "https://photojournal.jpl.nasa.gov/gallery/snt"
  ' Set HTML options
  doc.HtmlOptions.AddLinks = True
  doc.HtmlOptions.UseScript = True
  doc.HtmlOptions.PageCacheEnabled = False
  ' JavaScript is used to extract all links from the page
  doc.HtmlOptions.OnLoadScript = "var hrefCollection = document.all ? document.all.tags(""a"") : document.getElementsByTagName(""a"");" + "var allLinks = """";" + "for(i = 0; i < hrefCollection.length; ++i) {" + "if (i > 0)" + vbTab & "allLinks += "","";" + "allLinks += hrefCollection.item(i).href;" + "};" + "document.documentElement.abcpdf = allLinks;"
  ' Array of links - start with base URL
  Dim links As New ArrayList()
  links.Add(theURL)
  Dim i As Integer = 0
  While i < links.Count
    ' Stop if we render more than 20 pages
    If doc.PageCount > 20 Then
      Exit While
    End If
    ' Add page
    doc.Page = doc.AddPage()
    Dim theID As Integer = doc.AddImageUrl(TryCast(links(i), String))
    ' Links from the rendered page
    Dim allLinks As String = doc.HtmlOptions.GetScriptReturn(theID)
    Dim newLinks As String() = allLinks.Split(New Char() {","C})
    For Each link As String In newLinks
      ' Check to see if we allready rendered this page
      If links.BinarySearch(link) < 0 Then
        ' Skip links inside the page
        Dim pos As Integer = link.IndexOf("#")
        If Not (pos > 0 AndAlso links.BinarySearch(link.Substring(0, pos)) >= 0) Then
          If link.StartsWith(theURL) Then
            links.Add(link)
          End If
        End If
      End If
    Next
    ' Add other pages
    While True
      doc.FrameRect()
      If Not doc.Chainable(theID) Then
        Exit While
      End If
      doc.Page = doc.AddPage()
      theID = doc.AddImageToChain(theID)
    End While
    System.Math.Max(System.Threading.Interlocked.Increment(i),i - 1)
  End While
  ' Link pages together
  doc.HtmlOptions.LinkPages()
  ' Flatten all pages
  Dim i As Integer = 1
  While i <= doc.PageCount
    doc.PageNumber = i
    doc.Flatten()
    System.Math.Max(System.Threading.Interlocked.Increment(i),i - 1)
  End While
  ' Save the document
  doc.Save(Server.MapPath("HtmlOptionsJavaScript.pdf"))
End Using

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Also see example code in: ABCpdf Paged HTML Example.