Discussion on Remote Data Acquisition Technology of Brushless newest

Refresh Technology has gone through several stages:

1. Add a key to the HTML file header so that the page jumps to the specified page (including itself) after the specified time );

For example:

<Meta http-equiv = "refresh" content = "30">

Ii. Use the framework and regularly refresh the framework content in the JS script.

The above two methods will reload the page, that is, refresh. It doesn't feel good! So the new anti-bot technology emerged.

3. It is an alternative to the second method.

Set the length and width of one of the many frameworks to 0 to make them invisible. Then, refresh the hidden framework content regularly through the script, and then "write" the framework content to the browsed framework. Most early chat rooms used this technology.

In the real sense, the implementation of the new technology is still the following two technologies, they can even achieve local Refresh:

4. XMLHTTP technology: You can access ASP pages, aspx pages, and WebServices through XMLHTTP.

<Script language = "JavaScript">
Function re ()
{
VaR HTTP = new activexobject ("Microsoft. XMLHTTP ");
HTTP. Open ("get", ".../advertisement/3.htm", false );
HTTP. Send ();
VaR STR = http. responsetext;
T. innerhtml = STR;
}
</SCRIPT>
<Span id = T> </span>

5. WebService: Use the WebService. HTC component to access the Web service.

VaR OBJ;
Function Init (OBJ, op, ID)
{
OBJ = OBJ;
OBJ. useservice ("admin/dataoperation. asmx? WSDL "," getbody ");
OBJ. getbody. callservice (show, op, ID );
}

Function show (result ){
OBJ. innerhtml = result. value;
}

6. remoting: remoting can also be used to implement a new brushless Newest technology. Because the remoting component can provide multiple access methods, including HTTP, when accessed as HTTP, it is equivalent to a WebService.