在执行事件时，通常可取的做法是将私有数据和持久性数据附加到对象中。JavaScript 不支持“私有”实例数据，但是支持允许内部函数访问外部变量的闭包。在事件中，闭包非常适用于访问通常不附加到发生事件的对象的变量。

以下示例在事件中使用了函数闭包将加密讯息分配给一组标记。点击每个标记将会看到加密讯息的一部分，该讯息并不包含在标记本身内。
代码如下:
var map;
function initialize() {
var myLatlng = new google.maps.LatLng(-25.363882,131.044922);
var mapOptions = {
zoom: 4,
center: myLatlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
}

map = new google.maps.Map(document.getElementById("map_canvas"), mapOptions);

// Add 5 markers to the map at random locations.
var southWest = new google.maps.LatLng(-31.203405,125.244141);
var northEast = new google.maps.LatLng(-25.363882,131.044922);
var bounds = new google.maps.LatLngBounds(southWest,northEast);
map.fitBounds(bounds);
var lngSpan = northEast.lng() - southWest.lng();
var latSpan = northEast.lat() - southWest.lat();
for (var i = 0; i < 5; i++) {
var location = new google.maps.LatLng(southWest.lat() + latSpan * Math.random(),
southWest.lng() + lngSpan * Math.random());
var marker = new google.maps.Marker({
position: location,
map: map
});
var j = i + 1;
marker.setTitle(j.toString());
attachSecretMessage(marker, i);
}
}

// The five markers show a secret message when clicked
// but that message is not within the marker's instance data.
function attachSecretMessage(marker, number) {
var message = ["This","is","the","secret","message"];
var infowindow = new google.maps.InfoWindow(
{ content: message[number],
size: new google.maps.Size(50,50)
});
google.maps.event.addListener(marker, 'click', function() {
infowindow.open(map,marker);
});
}

这段代码是从google官方里面复制下来的

接下来我要实现从数据库中读取经纬度、地址信息，在google map上进行标注并单击标注出现信息

要实现多点标注，以上代码可以参考
代码如下:

var map;
window.onload =function load() {

var number='<%=number %>';//获取后台cs的pubilc的number的值
var address = new Array()
var weidu=new Array();
var jingdu=new Array();
var chepai = new Array();
<% for(int i=0;i

weidu.push('<%=lan[i]%>');//从后台cs获取经纬度的值
jingdu.push('<%=lon[i]%>');
address.push('<%=addr[i]%>');
chepai.push('<%=carnum[i] %>');
// var wei ;
// wei = chepai['<%=i%>'];
// alert(wei);
<% } %>

var Latlng = new google.maps.LatLng(weidu[0], jingdu[0]);
// var myLatlng = new google.maps.LatLng(25.273566, 110.290195);
var myOptions = {
zoom: 8,
center: Latlng,
mapTypeId: google.maps.MapTypeId.ROADMAP
};
map = new google.maps.Map(document.getElementById("map_canvas"), myOptions);////初始化一个地图实例

for(var j=0;j，其实单纯的js不需要，跟C差不多就可以了
{
var lat = weidu[j];
var lng = jingdu[j];
var addre = address[j];
var chepaihao = chepai[j];
// alert(j);
// alert(lat);
// var image = 'Image/webcam.png';
//设置标志点
var myLatlng = new google.maps.LatLng(weidu[j ], jingdu[j ]);
var h = chepaihao;
var tit = h.toString();
var marker = new google.maps.Marker({
position: myLatlng,
map: map,
// icon: "http://google-maps-icons.googlecode.com/files/yellow08.png",
// icon: image, //通过icon可以设定自己想显示的图标，不设置则显示Google map默认的图标
title: tit //title表示鼠标放到marker上要显示的值。
});
attachSecretMessage(marker, j,addre,lat,lng);

}

}

function attachSecretMessage(marker, number,addre1,lat1,lng1) {

// var message = ["This", "is", "the", "secret", "message"];
var infowindow = new google.maps.InfoWindow(
{ content: "地址: " + addre1 + "
"+ "经纬度："+ lat1 + "，"+ lng1 +"",
size: new google.maps.Size(50, 50)
});
// infowindow.setContent("地址:"+ addre1 +"经度:" +lat1 + "纬度："+lng1);
//点击弹出信息窗口
google.maps.event.addListener(marker, 'click', function () {
infowindow.open(map, marker);
});
}

cs后端代码：
代码如下:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
public partial class Default2 : System.Web.UI.Page
{
public double[] la = new double[25];
public double[] ln = new double[25];
public int[] id = new int[25];
public string[] addr = new string[25];
public int number;

protected void Page_Load(object sender, EventArgs e)
{
string mycnnConnectionString1 = System.Configuration.ConfigurationManager.ConnectionStrings["testconect"].ConnectionString; //创建连接字符串
SqlConnection mycnn1 = new SqlConnection(mycnnConnectionString1);
mycnn1.Open();
SqlCommand cmd1 = new SqlCommand("select L_ID,L_Lantitude,L_Longitude,L_Address from LatestPosition ", mycnn1);
SqlDataReader dr1 = cmd1.ExecuteReader();
int k2 = 0;
int k3 = 0;
int k4 = 0;
int k1 = 0;
// string buf1 = "";
double buf2 = 0;
double buf3 = 0;
int buf4 = 0;
string buf1 = "0";
while (dr1.Read())
{
//lat
buf2 = (double)dr1["L_Lantitude"];
la[k2] = buf2;
k2++;
//lng
buf3 = (double)dr1["L_Longitude"];///数据库读取float型的数据要用double
ln[k3] = buf3;
k3++;
//id
buf4 = (int)dr1["L_ID"];
id[k4] = buf4;
k4++;
buf1 = dr1["L_Address"].ToString();
addr[k1] = buf1;
k1++;

}
number = k4;
dr1.Close();
mycnn1.Close();

}

}