How to Execute a JavaScript Code on a TWebBrowser Document

The TWebBrowser Delphi control provides access to the Web browser functionality from your Delphi applications.

Here's how to execute a custom script (JavaScript or VBScript) function on a HTML document loaded in the TWebBrowser control:

uses MSHTML_TLB, SHDocVw;

procedure ExecuteScript(doc: IHTMLDocument2; script: string; language: string) ;
begin
   if doc <> nil then
   begin
     if doc.parentWindow <> nil then
       doc.parentWindow.ExecScript(script, Olevariant(language)) ;
   end;
end;

Usage (in some Button OnClick event handler, for example):

var
   script : string;
begin
   //locate the first element with ID attribute = "main" and show its tag

   script := 'var elemMain = document.getElementById("main") ; if (elemMain != null) { alert(elemMain.tagName) ; }';

   ExecuteScript(EmbeddedWB1.Document as IHTMLDocument2, script, 'javascript')
end;

Note: More TWebBrowser Tips'n'Tricks!

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