当前位置: 首页 > 图文教程 > 网络编程 > ASP > javascript asp教程创建数据库连接

ASP
ASP实例:读取xml文件的程序
asp实现rar压缩和解压缩源代码
关于ASP中脚本执行顺序的讲解
用asp程序读取网站的alexa世界排名
初学ASP编程易犯的一个错误要注意
ASP实现SQL语句日期格式的加减运算
通过启动脚本来感受ASP的力量
ASP SCRIPT: 计数器(使用GrapShot组件)
学以致用 驳“ASP低能论”
ASP分页显示Recordset数据
ASP编程代码:隐藏图片的真实地址
ASP网站Server object error的解决办法
用ASP对网页进行限制性的访问
把网页中的电话号码生成图片的ASP程序
ASP实现文件直接下载
用ASP显示ACCESS数据库的的GIF图象
ASP分页和日期格式化为RFC822格式的办法
实例:ASP与ACCESS链接
ASP程序直接连接MYSQL数据库
ASP连接MSSQL的错误: 拒绝访问

ASP 中的 javascript asp教程创建数据库连接


出处:互联网   整理: 软晨网(RuanChen.com)   发布: 2009-09-13   浏览: 114 ::
收藏到网摘: n/a

While this section is devoted to ASP database utilization, it very important to remember that this web site is not intended to be a thorough ASP resource. Remember, the focus of this site is strictly limited to how to use JavaScript as your primary scripting language for ASP.

You'll see how to construct connection strings in JavaScript, use JavaScript loops to manipulate recordsets, convert the JavaScript Date Object into a format that databases can accept, and to some extent you'll see how to make SQL statements in JavaScript.

You can find a lot of good resources on database utilization. Those resources, coupled with the next four lessons, will be everything you need to write ASP JavaScript database applications.

The Connection Object:

The connection object is the link between the database and your ASP script. Remember, it's a created or instanciated object, so we can have two or more instances of Connection on one page. Connection has eight (8) methods, eleven (11) properties, nine (9) events, and finally it has two (2) properties. We will discuss three of the methods, one of the properties, and then we will forego the rest.

There are four common connections. 1) MDL 2) DSN 3) ODBC 4) OLE-DB. MDL stands for Microsoft Data Link. Don't use it. Also, please don't use a DSN; it's slow and outdated and nobody recommends it. ODBC is better, but it's not the best. The recommended connection type is OLE-DB. That's the type of connection you'll see demonstrated below.

Get Started:

Below is the script for Lesson 16. Don't try to understand it yet. We will slowly pick this thing apart down below.

<%@LANGUAGE="JavaScript"%>
<!-- METADATA TYPE="typelib"
FILE="C:\Program Files\Common Files\System\ado\msado15.dll" -->
<HTML>
<BODY>
<%
var myConnect = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=";
myConnect += Server.MapPath("\\");
myConnect += "\\GlobalScripts\\htmlColor.mdb;";
var ConnectObj = Server.CreateObject("ADODB.Connection");
var RS = Server.CreateObject("ADODB.Recordset");
var sql="SELECT ID, colorName, hexValue FROM colorChart;";
ConnectObj.Open (myConnect);
RS.Open(sql,ConnectObj,adOpenForwardOnly,adLockReadOnly,adCmdText);
Response.Write("<TABLE BORDER=\"1\" CELLSPACING=\"0\">\r");
Response.Write("<TR><TH>ID</TH><TH>colorName</TH>");
Response.Write("<TH>hexValue</TH></TR>\r");
while (!RS.EOF)	{	Response.Write("<TR><TD>" +RS("ID")+ "</TD><TD BGCOLOR=\"#");	Response.Write( RS("hexValue")+ "\">" + RS("colorName") );	Response.Write("</TD><TD>" +RS("hexValue")+ "</TD></TR>\r");	RS.MoveNext();	}
Response.Write("</TABLE>\r");
RS.Close();
ConnectObj.Close();
RS = null;
ConnectObj = null;
%>
</BODY>
</HTML>

Click Here to run the script in a new window.

Connection String:

This is by no means the most sophisticated database application ever built, but it will demonstrate everything we need to do. Let's start by looking at the connection string reprinted below.

var myConnect = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=";
myConnect += Server.MapPath("\\ASP")
myConnect += "\\GlobalScripts\\htmlColor.mdb;";

That does look different than a VBScript connection string. As a matter of fact, let's compare.

Dim myVBconnect;
myVBconnect = "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=";
myVBconnect += Server.MapPath("\ASP")
myVBconnect += "\GlobalScripts\htmlColor.mdb;";

We already talked about escape characters in lesson 02. We won't revisit them here. Down below you'll see that we use myConnect as an argument in the Open() method.

Managing the Connection:

I want you to pay attention to the next four lines of code that I reprinted below. First we instanciate a Connection Object.

var ConnectObj = Server.CreateObject("ADODB.Connection");

Then we open the Connection.

ConnectObj.Open (myConnect);

Then the Connection Object becomes the second argument in the Recordset Open() method.

RS.Open(sql,ConnectObj,adOpenForwardOnly,adLockReadOnly,adCmdText);

And lastly, when we are finished with the Connection, we close it.

ConnectObj.Close();

Next Up:

There is a lot of code left unexplained in this example. We'll repeat the same script in lesson 17 and go over most of what we left out the first time through.