第一种:这种简单,但是会出现闪屏
Response.Write("<script language=javascript>alert(\"OK!\");</script>");
第二种:这种不会出现闪屏
/// <summary>
/// 弹框提示
/// </summary>
/// <param name="msg"></param>
/// <param name="webPage"></param>
public static void AlertMsg(string msg, Page webPage)
{
string strScript = "";
strScript = ("<script language=javascript>");
strScript += ("alert('" + msg + "');");
strScript += ("</script>");
webPage.ClientScript.RegisterStartupScript(webPage.GetType(), "MsgBox", strScript);
}