| This page demonstrates: |
Reading of special variables, in this case HTTP HEADER variables. Mapping to PLC variables. |
First page of this demo :
Reading and writing various variable types
In order to request automatic transfer of HTTP Header values into PLC variables, the AWP statement AWP_In_Variable has to be used.
If the PLC variable should not be a global variable with the same name as the header variable (e.g. "HEADER:From" may exist, however, some names may be too long for a PLC variable),
then a mapping to another PLC variable (which may be a structure component within a DB) has to be defined with the "Use"-Option.
The PLC variables should be of type "string" to be able to hold all values of the Header variables.
An example definition from this page:
|
<!-- AWP_In_Variable Name="HEADER:From" Use='"HttpInfoVariables".headerRequest.From' -->
|
| HTTP Request HEADER | | Value |
|---|
| Accept | = | :="HttpInfoVariables".headerRequest.accept: |
| Accept-Encoding | = | :="HttpInfoVariables".headerRequest.acceptEncoding: |
| Accept-Language | = | :="HttpInfoVariables".headerRequest.acceptLanguage: |
| Connection | = | :="HttpInfoVariables".headerRequest.connection: |
| Cookie | = | :="HttpInfoVariables".headerRequest.cookie: |
| Host | = | :="HttpInfoVariables".headerRequest.host: |
| Referer | = | :="HttpInfoVariables".headerRequest.referer: |
| User_Agent | = | :="HttpInfoVariables".headerRequest.userAgent: |