繁體中文当前位置: 首页 > 图文教程 > 网络编程 > ASP > javascript asp教程Recordset记录
- ASP
- 简单ASP论坛DIY
- 如何防止页面中的敏感信息被提取
- asp创建对象及中文显示解决技巧
- 基础开发入门级：JSP与ASP的比较
- 数据库受到限制怎么办？
- ASP初学者常犯的几个错误
- Asp定时执行操作、Asp定时读取数据库(网页定时操作详解)
- ASP优化：非常实用的ASP提速技巧五则
- ASP教程：解决ASP脚本运行超时的方法
- ASP安全：简单学习ASP连接数据库方法
- 简单一招用ASP实现对IE地址栏参数的判断
- asp控制xml数据库的6段非常的经典代码
- ASP进阶：验证身份证号是否正确的代码
- ASP教程：使用ASP生成图片彩色校验码
- ASP进阶：用ASP判断文件地址是否有效
- ASP进阶：用asp做的简单搜索引擎代码
- ASP实例 挂QQ的网页源代码ASP/PHP
- ASP答疑 解决ASP脚本运行超时的方法
- 轻轻松松破解开别人ASP木马密码的方法
- 用ASP操作Access数据库 ADOX的使用
ASP 中的 javascript asp教程Recordset记录
出处:互联网 整理: 软晨网（RuanChen.com） 发布: 2009-09-13 浏览: 67 ::
收藏到网摘: n/a
Recordset is another created/instanciated Object. It is a collection of data taken from a database. Recordset has 26 properties, 25 methods, 11 events, and two (2) collections. The vast majority of Recordset is beyond the scope of this web site.
Quick Aside:
The database we are using for lesson 16 and lesson 17 is an MS Access 2000 file (not the best database for large sites). The file is called htmlColor.mdb and it has a single Table called colorChart. The database Table has three columns and they are called ID, colorName, and hexValue.
The illustration below shows how we will cycle through these records.
|
|
|
In this example we cycle through the records row by row. We will use the MoveNext() Method to go from record #1 to #2, etc. Then, we will access specific data in each row by using the column name.
Get Started:
Below is the script for Lesson 17. It's exactly the same as the script for lesson 16. The difference is that we will focus on those lines of code that deal with Recordsets.
<%@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.
The DLL:
We'll dissect the Recordset statements from top to bottom. In this case that means starting with the Dynamic Link Library.
<!-- METADATA TYPE="typelib" FILE="C:\Program Files\Common Files\System\ado\msado15.dll" -->
What in the world is a DLL? A Dynamic Link Library holds values without tying up memory. Here's how it works. If you try to use a variable that is undefined, ASP will first look it up in the DLL. You'll notice in the
Managing the Recordset:
First we must instanciate a Recordset, which we do in the little snippet below.
var RS = Server.CreateObject("ADODB.Recordset");
Next we create a Text Command. The text in question comes in the form of S.Q.L. (Structured Query Language). SQL is beyond the scope of this web site, but the command below means select ID, colorName and hexValue from the colorChart Table.
var sql="SELECT ID, colorName, hexValue FROM colorChart;";
Then we open the Recordset. The five arguments in order are: source, connection, cursor type, lock type, and options .
RS.Open(sql,ConnectObj,adOpenForwardOnly,adLockReadOnly,adCmdText);
Using a loop, we tell ASP to do certain things for as long as we haven't hit EOF, which means End of File.
while (!RS.EOF)
Next, we access specific collums in the Recordset by name.
Response.Write( RS("hexValue") + "\">" + RS("colorName") );
Then we move down from one row of records to the next.
RS.MoveNext();
Finally, when we reach EOF, the loop relinquishes control and we can close the Recordset Object.
RS.Close();
The Rest of The Story:
This is by no means a complete lesson on Recordsets; it wasn't meant to be. The rest of the story on Recordsets is out there, on the internet, and in books. There is one other thing we have to talk about with Recordsets. We do that in lesson 18.
评论 (0) All
