WriteValue Function
The WriteValue function writes a single key/value pair (a value and a unique name for that value) to your modular output system outputs.
The following parameters are supported…
| Parameter | Default | Meaning |
|---|---|---|
| name | The name (key) for the key/value pair. This may contains '/' symbols if the value is hierarchial | |
| value | The value for the key/value pair. This should be a number or string | |
| options | None | Options to pass to the function (see Options) |
| force | False | If true, forces the write to take place even if there is no change in value |
| config | None | Contains additional outputs/destinations |
Parameters
Name & Value
The name and value are simple - it's the value you want to write, and a unique identifying name for that value.
oe.WriteValue("Temperature5",25.2)
Options
Options are passed as a dictionary of option names and values.
| Option Name | Meaning |
|---|---|
| datatype | Forces a certain data type - for example, 'text' |
Other options can be used as conditions for different output methods. For example, you might write a value with the following options…
oe.WriteValue("Temperature1",22.1,options={"group": "low_priority"})
…and rules inside your output configuration can then ensure that the output is treated as a low rather than high-priority value.
Force
By default, changes aren't written to the destinations if the value hasn't changed. The force parameter tells the system to write the results to the destination, even if no change has happened.
Config
In some cases, your application might have a specific destination in mind for the results. This allows you to send a dictionary containing output configuration details.
This lets you provide a UI to the user setting up specific, per-point delivery rules.
oe.WriteValue("Pressure5",1126,config=[{"method": "text", "path": "c:\testing\sample.txt"}])