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Ajax模拟留言

2012-03-04 19:15 85 查看

create table UserInfo
(
username varchar(20),
userpwd varchar(20)
)

insert into UserInfo values('administrator','123456')
create table ChatInfo
(
id int identity(1,1)  primary key,
[name] varchar(20),
context varchar(20),
chattime datetime
)

public class Userinfo
{
private string name;

public string Name
{
get { return name; }
set { name = value; }
}
private string pwd;

public string Pwd
{
get { return pwd; }
set { pwd = value; }
}
}

public class ChatInfo
{
private string id;

public string Id
{
get { return id; }
set { id = value; }
}
private string context;

public string Context
{
get { return context; }
set { context = value; }
}
private string name;

public string Name
{
get { return name; }
set { name = value; }
}
private string time;

public string Time
{
get { return time; }
set { time = value; }
}

public override string ToString()
{
return string.Format("{0} 说 {1} 时间{2}", name, context, time);
}
}

public class DBHelper
{
private SqlConnection sqlconn = null;
private SqlCommand sqlcmd = null;
private SqlDataReader sqlread = null;
private static DBHelper db = null;
private DBHelper()
{
sqlconn = new SqlConnection(ConfigurationManager.ConnectionStrings["sqlDB"].ToString());

}
/// <summary>
/// 单例
/// </summary>
/// <returns></returns>
public static DBHelper createInstance()
{
if (db == null)
{
db = new DBHelper();
}
return db;
}
public bool checkLogin(Userinfo user)
{
string sql = string.Format("select count(*) from userinfo where username='{0}' and userpwd='{1}'",user.Name,user.Pwd);
sqlcmd = new SqlCommand(sql,sqlconn);
try
{
sqlconn.Open();
return (int)sqlcmd.ExecuteScalar() == 1;
}
catch
{

return false;
}
finally
{
sqlconn.Close();
}
}
//发言
public bool sendChat(ChatInfo chat)
{
string sql = string.Format("insert into ChatInfo values('{0}','{1}','{2}')",chat.Context,chat.Name,DateTime.Now.ToString());
sqlcmd=new SqlCommand(sql,sqlconn);
try
{
sqlconn.Open();
return sqlcmd.ExecuteNonQuery() > 0;
}
catch
{

return false;
}
finally
{
sqlconn.Close();
}
}
//显示
public List<ChatInfo> GetAllInfo()
{
string sql = "select *from Chatinfo order by chattime";
sqlcmd = new SqlCommand(sql,sqlconn);
try
{
sqlconn.Open();
sqlcmd = new SqlCommand(sql, sqlconn);
sqlread = sqlcmd.ExecuteReader();
List<ChatInfo> list = new List<ChatInfo>();
while (sqlread.Read())
{
ChatInfo chat = new ChatInfo();
chat.Id = sqlread[0].ToString();
chat.Context = sqlread[1].ToString();
chat.Name = sqlread[2].ToString();
chat.Time = sqlread[3].ToString();
list.Add(chat);
}
return list;
}
catch (Exception)
{

throw;
}
finally
{
sqlconn.Close();
}
}
}

<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title></title>
<script type="text/javascript">
var xmlHttp;
function createDemo() {
if (window.ActiveXObject) {
var ieArr = ["Msxml2.XMLHTTP.8.0", "Msxml2.XMLHTTP.7.0", "Msxml2.XMLHTTP.6.0", "Msxml2.XMLHTTP.3.0", "Msxml2.XMLHTTP", "Microsoft.XMLHTTP"];
for (var i = 0; i < ieArr.length; i++) {
try {
xmlHttp = new ActiveXObject(ieArr[i]);
}
catch (e) { } //抛异常，直到找到合适的版本
}
}
else if (window.XMLHttpRequest) {
xmlHttp = new XMLHttpRequest();
}
}
//登录
function doDemo() {
var name = document.getElementById("txtName").value;
var pwd = document.getElementById("txtPwd").value;
if (name.length < 3) {
alert("用户名不能少于3位!");

}
else if (pwd.length < 6) {
alert("用户密码不能少于6位!");

}
else {
createDemo();
xmlHttp.onreadystatechange = disDemo; //触发事件
var url = "WebChat.aspx?name=" + name + "&pwd=" + pwd;
xmlHttp.open("GET", url, true);
xmlHttp.send();
}
document.getElementById("divDis").innerHTML = "";

}
//发言
function sendDemo() {
var chat = document.getElementById("txtChat").value;
var name = document.getElementById("userName").value;
if (chat.length == 0) {
alert("不能空发信息");
}
else {
createDemo();
//异步请求伴随着5种状态的产生，只有一个事件onreadystatechange发生
xmlHttp.onreadystatechange = disDemo;
var url = "InsertDemo.aspx?name=" + name + "&chat=" + chat;
//加载
xmlHttp.open("GET", url, true);
//发送
xmlHttp.send();
}
}
//显示
function disDemo() {
if (xmlHttp.readyState == 4)// 0 － （未初始化）还没有调用send()方法
//1 － （载入）已调用send()方法，正在发送请求
// 2 － （载入完成）send()方法执行完成，已经接收到全部响应内容
//   3 － （交互）正在解析响应内容
// 4 － （完成）响应内容解析完成，可以在客户端调用了
{
if (xmlHttp.status == 200)//编号200表示成功
{
//responsetext 以字符串形式返回服务器的响应，responsexml 以XML形式返回服务器的响应
document.getElementById("divLogin").innerHTML = xmlHttp.responsetext;
}
}
}
</script>
</head>
<body>
<div id="divDis">
<table border="1" align="center">
<tr>
<td colspan="2" align="center">
用户登录
</td>
</tr>
<tr>
<td>
用户名称
</td>
<td>
<input id="txtName" type="text" />
</td>
</tr>
<tr>
<td>
用户密码
</td>
<td>
<input id="txtPwd" type="password" />
</td>
</tr>
<tr>
<td colspan="2" align="center">
<input id="btnLogin" type="button" value="登录" onclick="doDemo();" />
</td>
</tr>
</table>
</div>
<div id="divLogin"></div>
</body>
</html>

public partial class InsertDemo : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

if (!IsPostBack)
{
string name = Request["name"];
string chat = Request["chat"];
ChatInfo chatInfo = new ChatInfo();
chatInfo.Name = name;
chatInfo.Context = chat;
if (DBHelper.createInstance().sendChat(chatInfo))
{
//Response.Write("发言成功!");
Response.Write("欢迎 " + name + "<br/><br/><br/>");
Response.Write("<input id='userName' type='hidden' value=" + name + " />");
foreach (ChatInfo demo in DBHelper.createInstance().GetAllInfo())
{
Response.Write(demo.ToString() + "<br/>");
}

Response.Write("<input id='txtChat' type='text' /><input id='btnSend' type='button' value='发言' onclick='sendDemo();' />");
}
else
{
Response.Write("发言失败!");
}

}
}
}

public partial class WebChat : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string name = Request["name"];
string pwd = Request["pwd"];
Userinfo user = new Userinfo();
user.Name = name;
user.Pwd = pwd;
if (DBHelper.createInstance().checkLogin(user))
{
Response.Write("欢迎 " + name + "<br/><br/><br/>");
Response.Write("<input id='userName' type='hidden' value=" + name + " />");
foreach (ChatInfo chat in DBHelper.createInstance().GetAllInfo())
{
Response.Write(chat.ToString() + "<br/>");
}
Response.Write("<input id='txtChat' type='text' /><input id='btnSend' type='button' value='发言' onclick='sendDemo();' />");
}
else
{
Response.Write("用户名或密码错误!");
}
}
}
}

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标签： ajax string xmlhttprequest input globalization function

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