changing the onclick property dynamically?

nerssi · September 19th, 2004, 01:04 AM

hi all,

I want to change the method name, I'm calling in an element on my page.
and I really need to pass a value through that method. It does work,but not so normally!?(pretty strange!)
assume I have a
<input type="button" id="x" onclick="">
now somewhere in the code, assuming we have a method 'y' which accepts an object as input,I try to change the onclick this way:

Neither works:

x.onclick=y(str);
nor
x.onclick=y("'"+str+"'");

:(

joefawcett · September 19th, 2004, 04:55 AM

Does str contain the value to be passed to the mathod, or it it the parameter name?

Code:

x.onclick = function{y(str);};

will evaluate str at run time and call y.

Code:

x.onclick = new Function(str, "y(" + str + ");");

will evaluate str now to be called later.

There are a number of other options if neither of these is what you meant.

--

Joe

--

Joe (Co-author Beginning XML, 3rd edition)

nerssi · September 19th, 2004, 06:02 AM

I need the second choice(evaluating first)
But using your code,the result would be a compilation error:Expected Identifier.

I must also say that I'm using the statement in an eval method as follows:

str="";
alert("x"+i+".onclick=new Function(str,\"back(\"+str+\");\")");
eval("x"+i+".onclick=new Function(str,\"back(\"+str+\");\")");

the message in alert box is just like the statement you sent for evaluating the str first!?

alert--> x1.onclick=new function(str,"back("+str+");")
Note:you know in eval I shouldn't put a ';' at the end but I tried with ';' at the ending too and it didn't work.

I just tried it out of eval and faced the same error.I tried the 'f' in Function in both cases(f and F) and just another error.

help please! I need it badly!

joefawcett · September 19th, 2004, 07:50 AM

You'll have to show more incontext. Works fine for me. I would never use eval in these circumstances, it not necessary and is a huge performance killer as well as a memory hog.

--

Joe

nerssi · September 19th, 2004, 08:43 AM

Here's a complete sample code with the error I mentioned just to show you my problem.
Please just copy paste the entire thing and tell me what's wrong.
I'm in a bit hurry

<HTML>
<HEAD>
<meta name=vs_targetSchema content="HTML 4.0">
<TITLE></TITLE>
<META NAME="GENERATOR" Content="Microsoft Visual Studio">
<META HTTP-EQUIV="Content-Type" content="text/html; charset=UTF-8">
<script language="javascript">

</script>
</HEAD>
<BODY>
<table border="2" bordercolor="#cc3300">
<tr>
<td id="c1" onclick="a();">Sets the onclick of the next cell</td>
<td id="c2" onclick="b('1');">First calls nothing</td>
</tr>
</table>
</BODY>
</HTML>

nerssi · September 19th, 2004, 11:53 PM

Really? Ain't there anybody who can answer this one!?

ChrisScott · September 20th, 2004, 03:15 AM

Hey nerssi,

It should work if you change

Code:

c2.onclick=new Function(str, "b(" + str + ");");

to

Code:

c2.onclick=new Function("b(" + str + ");");

HTH,

Chris

nerssi · September 20th, 2004, 10:25 AM

I did my job completely elseway without changing the onclick property.
testing to see if it works is just a matter of copy and paste.
I'll try it later but I doubt it'll work...

nerssi · September 21st, 2004, 12:59 AM

I've just tried it out and it was successful!
such a pity I didn't learned it soon enough to use it when I really did need it.
thanks anyway :)