Client side drop down menu question

Looking at the documentation expalining the use of client side menus, including the drop down menu.

I was messing around trying to get the "Open", once clicked, to use javascript to open windows file explorer to open/pick a file.

I've got it to partially work... Using keystrokes Ctrl-O will open the file explorer yet clicking on the drop down's File/Open does nothing.

Not sure what I'm doing wrong here.

NOTE:  I had commented out the two &html lines in the Testing Method... and doing a Ctrl-O still work.

Why?

 /// Created using the page template: Default
Class PublisherDB.NewClass1 Extends %ZEN.Component.page
{

/// Class name of application this page belongs to.
Parameter APPLICATION;

/// Displayed name of this page.
Parameter PAGENAME;

/// Domain used for localization.
Parameter DOMAIN;

/// This Style block contains page-specific CSS style definitions.
XData Style
{
<style type="text/css">
</style>
}

/// This XML block defines the contents of this page.
XData Contents [ XMLNamespace = "http://www.intersystems.com/zen" ]
{
<page xmlns="http://www.intersystems.com/zen" title="">
<csMenuBar id="mainMenu" width="100%">
  <csMenuBarItem caption="File" contextKey="f" >
    <contextMenu id="fileMenu" >
      <csMenuItem icon="images/file.png" caption="New" key="Ctrl-N"
                  contextKey="n" onclick="alert('New requested');"  />
      <csMenuItem icon="/csp/broker/images/open.png" caption="Open..."
                  key="Ctrl-O" contextKey="o"
                  onclick="zenPage.Testing()" />
      <csMenuItem caption="Close" key="Ctrl-W"
                  contextKey="c" onclick="alert('Open requested');"  />
      <csMenuSeparator />
      <csMenuItem id="savePick" icon="/csp/broker/images/save.png"
                  iconDisabled="/csp/broker/user/images/save_g.png"
                  caption="Save" key="Ctrl-S" contextKey="s"
                  onclick="alert('Save requested');"  />
      <csMenuItem icon="/csp/broker/images/saveas.png" caption="Save as..."
                  contextKey="a" />
      <csMenuItem icon="/csp/broker/images/saveall.png" caption="Save All"
                  contextKey="l" />
      <csMenuSeparator />
      <csMenuItem icon="/csp/broker/images/print.png" caption="Print"
                  key="Ctrl-P" contextKey="p"
                  onclick="alert('Print requested');" />
      <csMenuItem caption="Print Preview..."  contextKey="v" />
      <csMenuItem caption="Print Setup..."  contextKey="r" />
      <csMenuSeparator />
      <csMenuItem caption="Recent Files"  contextKey="e" />
      <csMenuSeparator />
      <csMenuItem caption="Exit" contextKey="x" />
    </contextMenu>
  </csMenuBarItem>
  <csMenuBarItem caption="Edit" contextKey="e">
    <contextMenu id="editMenu" >
      <csMenuItem id="undoPick" icon="/csp/broker/images/undo.png"
                  caption="Undo" key="Ctrl-Z" altCaption="Can't undo"
                  contextKey="u" onclick="alert('undo');" />
      <csMenuItem id="redoPick" icon="/csp/broker/images/redo.png"
                  caption="Redo" key="Ctrl-Y" altCaption="Can't redo"
                  contextKey="r" onclick="alert('redo');" />
      <csMenuSeparator />
      <csMenuItem id="cutPick" icon="/csp/broker/images/cut.png"
                  caption="Cut" key="Ctrl-X" contextKey="t"
                  onclick="alert('cut');" />
      <csMenuItem id="copyPick" icon="/csp/broker/images/copy.png"
                  caption="Copy" key="Ctrl-C" contextKey="c"
                  onclick="alert('copy');"  />
      <csMenuItem id="pastePick" icon="/csp/broker/images/paste.png"
                  caption="Paste" key="Ctrl-V" contextKey="p"
                  onclick="alert('paste');"  />
      <csMenuSeparator />
      <csMenuItem caption="Fill" contextKey="i" onclick="alert('fill');" />
      <csMenuItem caption="Clear" contextKey="a" onclick="alert('clear');" />
      <csMenuItem caption="Delete..." key="delete"
                  contextKey="d" onclick="alert('delete');"  />
      <csMenuSeparator />
      <csMenuItem caption="Select all" key="Ctrl-A"
                  contextKey="l" onclick="alert('select all');" />
      <csMenuSeparator />
      <csMenuItem icon="/csp/broker/images/find.png" caption="Find..."
                  key="Ctrl-F" contextKey="f" onclick="alert('find');" />
      <csMenuItem caption="Find in Files" key="Ctrl-Shift-F"
                  onclick="alert('find next');" />
      <csMenuItem caption="Replace..." key="Ctrl-H" contextKey="e"
                  onclick="alert('replace');" />
      <csMenuItem icon="/csp/broker/images/goto.png" caption="Go to..."
                  key="ctrl-g" contextKey="g" onclick="alert('goto');" />
    </contextMenu>
  </csMenuBarItem>
</csMenuBar>

</page>
}

ClientMethod Testing()
{

&html<
<form method="post" enctype="multipart/form-data">>


&html<
<tr><td><input type="file"/></td>
</tr>>  

}

}