//以居中方式弹出窗口.
function openWindow(urlStr, width, height) {
    var ht = window.screen.availHeight;
    var wt = window.screen.availWidth;
    window.open(urlStr, '_blank', 'top='+ (ht - height)/2 + ',left=' + (wt - width)/2 + ',titlebar=yes,location=yes,status=yes,scrollbars=yes,menubar=yes,toolbar=yes,directories=no,resizable=yes,width=' + width + ',height=' + height);
}
//以居中方式弹出窗口.不含ToolBar
function openWindowWithoutToolbar(urlStr, width, height) {
    var ht = window.screen.availHeight;
    var wt = window.screen.availWidth;
    windowWithoutToolbar(urlStr, width, height, ht, wt);
}
//按指定位置弹出窗口.
function windowWithoutToolbar(urlStr, width, height, top, left) {
    window.open(urlStr, '_blank', 'top='+ (top - height)/2 + ',left=' + (left - width)/2 + ',titlebar=no,location=no,status=no,scrollbars=yes,menubar=no,toolbar=no,directories=no,resizable=yes,width=' + width + ',height=' + height);
}