What if yu pass null for a missing parameter?
Jamal
On 12/22/2012 11:35 PM, martin webster wrote:
Hi Chip,
Sorry, JScript does not except the ",,, true) "comma construct for passing
empty parameters. If I attempt to pass parameters in this way I will get a syntax error
at column 85. This is because to declare an empty parameter you have to first make it
known to the JScript interpreter and give it no value like so:
var Parm1, parm2;
Using square brackets in the line:
var MyHotkey = Keyboard.RegisterHotKey("Control-Shift-Windows-h",
"SpeakHelloWorld", [p1, p2], true);
Should be passing p1 and p2 as empty parameters as an array, to the call back
proc which is the way you should pass optional arguments s in JScript. The docs
state that the last parameter of a function can be an array to pass optional
arguments, or you can use an array to pass a a single list of optional
parameters.
I have tried to pass true as a parameter, by using the true literal to set p3
like so:
var p1, p2;
var p3 = true;
var MyHotkey = Keyboard.RegisterHotKey("Control-Shift-Windows-h",
"SpeakHelloWorld", [p1, p2,
p3]);
this fails to with the error:
"Line 4 Column 1 The specified function does not have the proper number or types of
parameters. < 0x8004E001 >". Line 4 is the hotkey declaration shown above.
When the code is written as in my first example like so:
// Detect if a key has been pressed twice in succession
var p1, p2;
var MyHotkey = Keyboard.RegisterHotKey("Control-Shift-Windows-h",
"SpeakHelloWorld", [p1, p2],
true);
function SpeakHelloWorld(firstPress)
{
Speak(firstPress);
if (!firstPress) {
Speak("Key pressed twice in succession");
}
}
the script fails, by failure I mean I am not getting any errors, the script
runs, but does not behave as expected. The first press parameter is not being
set to false which is happening in the VBScript example, the first press
parameter remains stubbornly set at true. The only other thing of interest
about this script is the use of the exclamation mark used in JScript as the Not
operator like so:
if (!firstPress) {
Speak("Key pressed twice in succession");
}
I can and have easily test that this is working by setting the true value to false in the
hotkey declaration, and this element of the script is working fine, in other words the
first press parameter when set to false in the hotkey declaration remains stubbornly set
to false, and I hear the message "key pressed twice in succession". I don't
know what to test and try next really. Hope some body can hhelp.
Warm regards.
Martin Webster.
I.T. Director for Kirklees Visual Impairment Network.
--- On Sat, 12/22/12, Chip Orange <[email protected]> wrote:
From: Chip Orange <[email protected]>
Subject: RE: help with JScript example
To: [email protected]
Date: Saturday, December 22, 2012, 9:01 PM
Hi Martin,
While I don't know Jscript at all, I suspect the problem is
your use of p1
and p2 when calling the RegisterHotKey method. I don't
know what the
significance of the brackets is, but in this case you don't
want any
parameters passed in the third and forth places at all (just
add commas
enough so you will end up with 5 parameters if that's
allowed in Jscript).
Passing parameters of any type in the third and forth places
will cause
filtering to occur, and cause a second parameter to be
necessary for your
routine which is to be called (which for some reason GW
makes be the first
parameter in your called routine).
So, I think your statement should look like:
var MyHotkey =
Keyboard.RegisterHotKey("Control-Shift-Windows-h",
"SpeakHelloWorld",,, true)
Hth,
Chip
-----Original Message-----
From: martin webster [mailto:[email protected]]
Sent: Saturday, December 22, 2012 8:16 AM
To: [email protected]
Subject: help with JScript example
Hi all,
I cannot get the following example to work using
JScript. Can somebody
help please.
// Detect if a key has been pressed twice in
succession
var p1, p2;
var MyHotkey =
Keyboard.RegisterHotKey("Control-Shift-Windows-h",
"SpeakHelloWorld", [p1, p2], true)
function SpeakHelloWorld(firstPress)
{
Speak(firstPress);
if (!firstPress) {
Speak("Key pressed twice in succession");
}
}
Warm regards.
Martin Webster.
I.T. Director for Kirklees Visual Impairment Network.
