VariableWriteActivity

Category: Common Steps Namespace: CMS.Plugin.FlowManagement.Domain.FlowBusiness.Activitys Base Class: BusinessActivity Module: FlowManagement.Domain

Overview

VariableWriteActivity is a node used to write external variables (such as PLC variables) in a flow. Inheriting from BusinessActivity, it writes values to variables via the IFlowVariableService.

Configuration Instructions

Property Name	Type	Required	Default Value	Description
CheckVariableName	bool	No	false	Whether to check variable configuration
WriteRetryCount	int	No	3	Write retry count
WriteRetryDelay	int	No	500	Write retry delay (milliseconds)
ParameterVariables	WriteParameterVariables	No	Empty Collection	Parameter variable collection

Parameter Variable Configuration

Property Name	Type	Description
WriteVariableName	string	Write Variable Name
WriteVariableValue	string	Fixed Value to Write
ReadParameterName	string	Key name to read value from flow context
ReadVariableName	string	Variable name to read value from
FlowItemKey	string	Flow Context Key
WriteIntoDataItems	bool	Whether to write to flow context
Sort	int	Sort Order

Usage Examples

{
  "Type": "VariableWriteActivity",
  "Name": "Write PLC Vars",
  "Alias": "WritePLCVars",
  "WriteRetryCount": 3,
  "WriteRetryDelay": 500,
  "ParameterVariables": [
    {
      "WriteVariableName": "DB1.StartSignal",
      "WriteVariableValue": "1",
      "WriteIntoDataItems": false
    },
    {
      "WriteVariableName": "DB1.ProductCode",
      "ReadParameterName": "ProductCode_Value",
      "WriteIntoDataItems": true
    }
  ]
}

Notes

• 💡 Supports batch writing of multiple variables
• 💡 Automatically retries on write failure
• 💡 Supports reading values from flow context or other variables
• ⚠️ Requires variable service configuration (IFlowVariableService)

Related Nodes

• VariableReadActivity: Variable Read Node
• VariableMonitorActivity: Variable Monitor Node

Update History

Date	Version	Description
2025-11-28	1.0	Initial version

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Last updated: 2025-11-28