asp.net在iframe中弹出信息并执行跳转问题探讨

/// <summary>
/// iframe 中，弹出信息并跳转
/// </summary>
/// <param name="msg"></param>
/// <param name="targetpagename"></param>
public static void responseshowmsg(string msg, string targetpagename)
{
string str = "<script> alert('{0}'); window.parent.frames[\"sysmain\"].location.href = '{1}'; </script>";
string urls = httpcontext.current.request.url.originalstring;
if (urls.lastindexof('?') > 0)
{
urls = urls.substring(0, urls.lastindexof('?')).replace(httpcontext.current.request.url.segments[httpcontext.current.request.url.segments.length - 1], targetpagename);
}
else
{
urls = urls.replace(httpcontext.current.request.url.segments[httpcontext.current.request.url.segments.length - 1], targetpagename);
}
str = string.format(str, msg, urls);
httpcontext.current.response.write(str);
}

protected void btnsave_click(object sender, eventargs e)
{
if (bll.roleadd(model, tempms))
{
cmvspcommon.messagebox.responseshowmsg( "保存成功！", "add.aspx");
}
else {
cmvspcommon.messagebox.show(this, "保存失败！");
}
}