Retrieving Hardware Information using Advanced JavaScript with Internet Explorer
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This is the third article in a series focusing on retrieving hardware information using JavaScript and presenting the same on a web page. You can directly copy and paste the code samples presented in this article into a file with the extension “.htm” and open in Internet Explorer 5.5+.
As I am using the “Web Based Enterprise Management” (WBEM) strategy of Microsoft, the samples will work only with IE 5.5+.
How to list all of a computer's available onboard devices using JavaScript
Now, let us try to develop a simple script (JavaScript) which shows how to retrieve the list of all on-board devices related to a computer. The entire code for the sample is as follows:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<title></title>
<meta name="GENERATOR" content="Microsoft Visual Studio .NET
7.1">
<meta name="vs_targetSchema" content="http://
schemas.microsoft.com/intellisense/ie5">
<script id="clientEventHandlersJS" language="javascript">
<!--
function Button1_onclick() {
var locator = new ActiveXObject ("WbemScripting.SWbemLocator");
var service = locator.ConnectServer(".");
var properties = service.ExecQuery("SELECT * FROM Win32_OnBoardDevice");
var e = new Enumerator (properties);
document.write("<table border=1>");
dispHeading();
for (;!e.atEnd();e.moveNext ())
{
var p = e.item ();
document.write("<tr>");
document.write("<td>" + p.DeviceType + "</td>");
document.write("<td>" + p.Description + "</td>");
document.write("<td>" + p.Enabled + "</td>");
document.write("<td>" + p.Tag + "</td>");
document.write("</tr>");
}
document.write("</table>");
}
function dispHeading()
{
document.write("<thead>");
document.write("<td>DeviceType</td>");
document.write("<td>Description</td>");
document.write("<td>Enabled</td>");
document.write("<td>Tag</td>");
document.write("</thead>");
}
//-->
</script>
</head>
<body>
<INPUT id="Button1" type="button" value="Button"
name="Button1" language="javascript" onclick="return Button1_onclick()">
</body>
</html>
In the above code “meta” tags are not necessary. They have been automatically added by Visual Studio. The above would automatically list all on-board devices belonging to a computer. It mainly lists the type of device, description, whether it is enabled or not and the device tag. To retrieve this information, I used a built-in class, “Win32_OnBoardDevice.”
The “for” loop I used in the above code iterates for every on-board device present in the system and finally retrieves only the properties of that on-board device.
In general, there will be many types of devices on board. The devices include video, SCSI controller, Ethernet (especially for LAN), and so on. The “Device Type” property explains the type of device being represented. The following is the table extracted from MSDN to provide you with an explanation of those values returned by “Device Type.”
Value | Meaning |
1 | Other |
2 | Unknown |
3 | Video |
4 | SCSI Controller |
5 | Ethernet |
6 | Token Ring |
7 | Sound |
Next: How to dig out a computer's processor information using JavaScript >>
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