留言本（4）写留言

看一下页面吧！

怎么实现的呢？主要是验证控件的使用。还有是使用request传递页面参数id. 

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="post.aspx.cs" Inherits="post" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>无标题页</title>
</head>
<body>
    <form id="form1" runat="server">
     <div align="center">
        <table border="1" style="width: 100%; height: 18%" bordercolor="#ffcc33">
            <tr>
                <td align="center"  valign="top" style=" height: 104px;">
                    <asp:Image ID="Image1" runat="server" ImageUrl="~/img/tupian.gif" /></td>
            </tr>
        </table>
   
    </div>
        <div style="text-align: center">
            <table style="width: 266px; height: 46px">
                <tr>
                    <td style="font-weight: bold; font-size: x-large;  color: #996600">
                        我要留言</td>
                </tr>
            </table>
        </div>
        <div style="text-align: left">
            <table border="1" bordercolor="#ffcc00" style="width: 100%; height: 271px">
                <tr>
                    <td style=" height: 1px; width: 113px;">
                        主题：</td>
                    <td style="width: 550px; height: 1px" valign="middle">
                        <asp:TextBox ID="TextBox4" runat="server" Width="307px"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox4"
                            ErrorMessage="*"></asp:RequiredFieldValidator></td>
                </tr>
                <tr>
                    <td style=" height: 1px; width: 113px;">
                        姓名：</td>
                    <td style="width: 550px; height: 1px" valign="middle">
                        <asp:TextBox ID="TextBox1" runat="server" Width="216px"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ControlToValidate="TextBox1"
                            ErrorMessage="*"></asp:RequiredFieldValidator></td>
                </tr>
                <tr>
                    <td style=" height: 18px; width: 113px;">
                        E-mail</td>
                    <td style=" height: 18px; width: 550px;">
                        <asp:TextBox ID="TextBox2" runat="server" Width="316px"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ControlToValidate="TextBox2"
                            ErrorMessage="*"></asp:RequiredFieldValidator>
                        <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="TextBox2"
                            ErrorMessage="邮件格式不正确" ValidationExpression="/w+([-+.']/w+)*@/w+([-.]/w+)*/./w+([-.]/w+)*"></asp:RegularExpressionValidator></td>
                </tr>
                <tr>
                    <td style=" height: 106px; width: 113px;" valign="top">
                        留言内容：</td>
                    <td style=" height: 106px; width: 550px;" valign="top">
                        <asp:TextBox ID="TextBox3" runat="server" Height="103px" TextMode="MultiLine" Width="502px"></asp:TextBox>
                        <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ControlToValidate="TextBox3"
                            ErrorMessage="*"></asp:RequiredFieldValidator></td>
                </tr>
                <tr>
                    <td style=" height: 115px;" align="center" valign="top">
                        &nbsp; 头像预览： &nbsp;</td>
                    <td style=" height: 115px; width: 550px;" align="left" valign="top">
                        &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;
                        &nbsp; &nbsp; &nbsp;<br />
                        &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;
                        &nbsp; &nbsp; &nbsp;<asp:Image ID="Image2" runat="server" Height="90px" Width="90px" />&nbsp;<br />
                    </td>
                    <tr>
                        <td style="height: 66px">
                        </td>
                        <td align="left" style="width: 550px; height: 66px" valign="top">
                        请选择头像：<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
                                <asp:ListItem>1.jpg</asp:ListItem>
                                <asp:ListItem>2.jpg</asp:ListItem>
                                <asp:ListItem>3.jpg</asp:ListItem>
                                <asp:ListItem>4.jpg</asp:ListItem>
                                <asp:ListItem>5.gif</asp:ListItem>
                                <asp:ListItem>6.gif</asp:ListItem>
                                <asp:ListItem>7.gif</asp:ListItem>
                            </asp:DropDownList></td>
                    </tr>
                   
                        <tr>
                        <td align="center" colspan="2" style="height: 26px">
                            <asp:Button ID="Button2" runat="server" Text="提交" OnClick="Button2_Click" />
                            &nbsp;&nbsp;&nbsp;
                            <asp:Button ID="Button1" runat="server" CausesValidation="False"
                                PostBackUrl="~/Default.aspx" Text="返回首页" />
                            <asp:Label ID="Label1" runat="server" Text="Label" Visible="False"></asp:Label></td>
                </tr>
            </table>
        </div>
        <asp:ValidationSummary ID="ValidationSummary1" runat="server" HeaderText="你至少有一个信息没有输入" EnableTheming="False" ShowMessageBox="True" ShowSummary="False" />
    </form>
</body>
</html>

要注意的是：返回首页的这个按扭，一定要设置CausesValidation="False"，不然的话单南击这个按扭也需要验证控件的验证。

看看代码吧！

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class post : System.Web.UI.Page
{
    int Artid;
    protected void Page_Load(object sender, EventArgs e)
    {
        Image2.ImageUrl = "pic/1.jpg";
        Artid=DB.ExecuteScalar("select count(*)from guestbook");//也可以用max函数
        if (Artid== 0)//  记录上一条记录的id，为0就是还没有一条留言
        {
            Artid = 1;
        }
        else
        {
            Artid = Artid + 1;
        }

    }
    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        for(int i=0;i<DropDownList1 .Items .Count ;i++)//实现图片选择
        {
            if (DropDownList1.Items[i].Selected)
            {
               
                Image2.ImageUrl ="pic/"+ DropDownList1 .Items [i].ToString ();//要注意="pic/"+ 
            }
        }
    }
    protected void Button2_Click(object sender, EventArgs e)//写入数据库，去看一下基类方法是怎么写的
    {
        DB.ExecuteNonQuery("insert into guestbook values("+Artid +",'"+TextBox1 .Text +"','"+TextBox2 .Text +"','"+TextBox3 .Text +"','"+System .DateTime .Now +"','"+Image2 .ImageUrl +"','"+TextBox4 .Text +"')");
        Label1.Text = "提交成功！";
    }
  
  
}
要是验证没通过的，就显示如下：

好了，这篇就到这儿了。