如何检查打开的窗口是否用javascript关闭？

Question

有没有什么办法可以检测到我打开的那个弹出窗口是关闭还是不关闭？

<script type="text/javascript"> 
// global variable for subwindow reference 
var newWindow; 
// generate and fill the new window 
function makeNewWindow() { 
    // make sure it isn't already opened 
     newWindow = window.open("http://www.google.com","sub","status,height=200,width=300"); 

} 

function checkWindow() { 
    if(newWindow.closed){ 
     document.write("Window has closed."); 
    } 
} 
</script> 
    <form> 
<input type="button" value="Create New Window" onclick="makeNewWindow();" /> 
<script> 
    checkWindow(); 
</script> 
</form> 

我希望当我关闭打开的窗口。函数checkWindow（）在“窗口已关闭”屏幕上打印。请给我一些帮助代码。在此先感谢

Answer 1

var win = window.open('http://www.google.com','google','width=800,height=600,status=0,toolbar=0'); 
    var timer = setInterval(function() { 
    if(win.closed) { 
    clearInterval(timer); 
    alert('closed'); 
    } 
}, 1000);