js判断是刷新还是关闭

这个方法检测到不是否点击了刷新按钮和在窗口标题栏右键菜单关闭和任务栏右键菜单关闭

 

 

代码

var  bClose  =   false ,bRefresh = false ;
document.onkeydown = function (){
     if ((event.altKey && event.keyCode == 115 ) || (event.ctrlKey && event.keyCode == 87 )) // 键盘关闭 alt+f4,ctrl+w
    {
        bClose = true ;
    }
     else   if (event.keyCode == 116 ) // 键盘刷新 F5
    {
        bRefresh = true ;
    }    
}
window.onunload = function (){
     if (bRefresh)
    {
        alert( ' F5 refresh ' );
    }
     else   if (bClose || window.event.clientY < 0 )
    {
        alert( " close " );
         return ;
    }
     else
    {
        alert( " refresh " );
    }
}