Using eval for contents retrieved with XMLHttpRequest( )

[knocte]

Hello.

I have always thought that the eval() function was very flexible and
useful. If I use it, I can define functions at runtime!!

However, I have found a case where eval() does not work properly. It
works, for example, when invoking functions (alert('hello') ), but not
for defining functions.

The case occurs when retrieving the javascript code with
XMLHttpRequest( ). It fails on Mozilla/Firefox and IE!

I will quote the code:

<script>
function RequestDocument (sURL, bAsync) {
var oXmlRequest;

/* branch for native XMLHttpRequest object */
if (window.XMLHttp Request) {
oXmlRequest = new XMLHttpRequest( );
oXmlRequest.ope n("GET", sURL, bAsync);
oXmlRequest.sen d(null);
}
/* branch for IE/Windows ActiveX version */
else if (window.ActiveX Object) {
oXmlRequest = new ActiveXObject(" Microsoft.XMLHT TP");
oXmlRequest.ope n("GET", sURL, bAsync);
oXmlRequest.sen d();
}

return oXmlRequest;
}

function EvalScriptFile( oDocument){
if (oDocument){

/* only if status shows "loaded" */
if (oDocument.read yState == 4) {

/* only if "OK" */
if (oDocument.stat us == 200) {
eval(oDocument. responseText);
}
else if (oDocument.stat us == 404) {
alert("File not found");
}
}
}
}

function LoadScriptFile( sURL){
var oScriptFileRequ est = RequestDocument (sURL,false);
EvalScriptFile( oScriptFileRequ est);
}



//this works:
eval("alert('he llo');function test(){ alert('test'); };");
test();

//but, if I put on a file (called mylib.js and located at the same
//dir as this file on the web server), the following contents:
// alert('hello2') ;
// function test2(){ alert('test2'); };
//
LoadScriptFile( "mylib.js") ;
test2();
//the first alert is called (hello2)! but debugger says
//that test2 is not defined!
// what happens??
</script>
Do anybody know why?? Thanks in advance.

Regards,

Andrew

--

[knocte]

Razzbar escribió:

So shall also be many users scratching their heads as their browsers
hang useless, because some cowboy figured that if you put your JS
functions on the server and use a synchronous call, you are guaranteed
they will come a'running ever time, and execute when you want them to,
not before.

If JS don't work, my sites fallback to the fact that they don't support
client-side scripting, then many browsers will be supported only because
of this.

Regards,

knocte

--

[knocte]

VK escribió:

The case occurs when retrieving the javascript code with
XMLHttpReques t(). It fails on Mozilla/Firefox and IE!

Actually XMLHTTP doesn't stay from "get XML or HTTP or whatever you'll
get in your head". It stays from "get XML data for HTML environment
(browser)". But I'm affraid that all hell broke loose already. Mr.
Knocte is getting his JavaScript this way, someone already tried to get
binary data stream. So soon I guess we'll see XMLHTTP used to download
music, pictures and "Star Wars Episode 3". So shall be it...

Actually, I think the feature should be just called "HttpReques t",
because nothing prevents me for getting anything I want with the Http
protocol using this.

Regards,

knocte

P.S.: Perhaps you should suggest to the responsible for DOM specs to
delete the accessibility to the ".responseT ext" attribute. That way
you'll be able to dictate how the technologies must be used.

--

[VK]

> Actually, I think the feature should be just called "HttpReques t",

because nothing prevents me for getting anything I want with
the Http protocol using this.

"Who can stop Hafiz from likening a ladybug to the Padishah"
An old Persian proverbe ;-)

<http://groups-beta.google.com/group/comp.lang.javas cript/browse_frm/thread/f6ce0a5e95d8bf3 0/ba5264709e33894 e?q=group:comp. lang.javascript +author:VK&rnum =19&hl=en#ba526 4709e33894e>