ASP.NET打开新页面而不关闭原来的页面

Respose.Write("<script language='javascript'>window.open('"+ url +"');</script>"); （打开简洁窗口）：
Respose.Write("<script language='javascript'>window.open('" + url + "','','resizable=1,scrollbars=0,status=1,menubar=no,toolbar=no,location=no, menu=no');</script>");

1. Response.Redirect("XXX.aspx",true)——直接转向新的页面，原窗口被代替;
2. Response.Write("<script>window.open('XXX.aspx','_blank')</script>")——原窗口保留，另外新增一个新页面;
3. Response.Write("<script>window.location='XXX.aspx'</script>")——打开新的页面，原窗口被代替;
4. Server.Transfer("XXX.aspx")——打开新的页面;
5. Response.Write("<script>window.showModelessDialog('XXX.aspx')</script>")——原窗口保留，以对话框形式打开新窗口;
6. Response.Write("<script>window.showModelDialog('XXX.aspx')</script>")——对话框形式打开新窗口，原窗口被代替;

也可以自己写方法：

public static void ShowMessage(System.Web.UI.Page page, string msg)
{
page.ClientScript.RegisterClientScriptBlock(page.GetType(), "a", "alert('" + msg.ToString() + "');", true);

}

调用的时候：
ShowMessage(this,"要显示的消息");

下面是整个类的代码你可以挑着用

using System;
using System.Collections.Generic;
using System.Text;

namespace WorkLogic
{
/// <summary>
/// 显示消息提示对话框。
/// </summary>
public class MessageBox
{
private MessageBox()
{
}

/// <summary>
/// 显示消息提示对话框

/// </summary>
/// <param name="page">当前页面指针，一般为this</param>
/// <param name="msg">提示信息</param>
public static void ShowMessage(System.Web.UI.Page page, string msg)
{
//page.RegisterStartupScript("message", "alert('" + msg.ToString() + "');");
page.ClientScript.RegisterClientScriptBlock(page.GetType(), "a", "alert('" + msg.ToString() + "');", true);

}
public static void ShowMessage(System.Web.UI.UserControl control, string msg)
{
control.Page.ClientScript.RegisterClientScriptBlock(control.Page.GetType(), "b", "alert('" + msg.ToString() + "');", true);
}

/// <summary>
/// 控件点击 消息确认提示框

/// </summary>
/// <param name="page">当前页面指针，一般为this</param>
/// <param name="msg">提示信息</param>
public static void ShowConfirm(System.Web.UI.WebControls.WebControl Control, string msg)
{
//Control.Attributes.Add("onClick","if (!window.confirm('"+msg+"')){return false;}");
Control.Attributes.Add("onclick", "return confirm('" + msg + "');");
}

/// <summary>
/// 显示消息提示对话框，并进行页面跳转

/// </summary>
/// <param name="page">当前页面指针，一般为this</param>
/// <param name="msg">提示信息</param>
/// <param name="url">跳转的目标URL</param>
public static void ShowAndRedirect(System.Web.UI.Page page, string msg, string url, string frame)
{
StringBuilder Builder = new StringBuilder();
Builder.Append("<script language='javascript' defer>");
Builder.AppendFormat("alert('{0}');", msg);
Builder.AppendFormat("top." + frame + ".location.href='{0}'", url);
Builder.Append("</script>");
page.ClientScript.RegisterStartupScript(page.GetType(), "message", Builder.ToString());

}
/// <summary>
/// 输出自定义脚本信息

/// </summary>
/// <param name="page">当前页面指针，一般为this</param>
/// <param name="script">输出脚本</param>
public static void ResponseScript(System.Web.UI.Page page, string script)
{
page.ClientScript.RegisterStartupScript(page.GetType(), "message", "<script language='javascript' defer>" + script + "</script>");
}
/// <summary>
/// 显示消息提示对话框，并进行页面跳转
/// <param name="page">当前页面指针，一般为this</param>
/// <param name="msg">提示信息</param>
/// <param name="url">跳转的目标URL</param>
public static void ShowAndRedirect(System.Web.UI.Page page, string msg, string url)
{
StringBuilder Builder = new StringBuilder();
Builder.Append("<script language='javascript' defer>");
Builder.AppendFormat("alert('{0}');", msg);
Builder.AppendFormat("top.location.href='{0}'", url);
Builder.Append("</script>");
page.ClientScript.RegisterStartupScript(page.GetType(), "message", Builder.ToString());

}

}

}