How to create a popup windown with javascript?

Question

Hi, every one,
I made a jsp program. I know we can use win.open, win.close to create, to close a popup window with javascript. But I don't know how to create a popup window ,display some message on this window and there is a button on it for closing this window. Just like follows:
int mark;
if(mark==1){
     create popup window, display some message, there is a
button and click it to close this window.
} else {
     display error message.
Any one can help me?
Thanks in advance.
peter

Answer 1

Hi, bdtjdc,
Thank you for your help and kindness.
You know, I am a new one in javascript. So,
1, I only know how to use alert(message) on current page and I don't know how use alert(message) on the next page because I
need to pass some datas from current jsp page to next one.
2, when I use the code you gave me as follows, there is no popup window and button:
if(mark==1){
%>
<script language="JavaScript">
message=message+'enter your message here...<br>';
message=message+'<form name="form1"><input type="button" name="close" value="close window"
onClick="window.close()"></form>';
message='enter your message here...<br>';
var actwin=window.open("","","menubar=0,width=300,height=300");
actwin.document.write(message);
actwin.document.close();
actwin.focus();
</script>
<%
} else {
error message;
if I use the code like this, We have the window and message on it, but there is no button on the window.
if(mark==1){
%>
<script language="JavaScript">
message='enter your message here...<br>';
var actwin=window.open("","","menubar=0,width=300,height=300");
actwin.document.write(message);
actwin.document.close();
actwin.focus();
</script>
<%
} else {
     error message;
What's the problem? Please.
Thanks again.
Peter