Date Calculation/Add Days to a DateTime Attribute

Workflows
1

Hi,

I’d like a workflows to calculate a target date from the raised date, instead of when the workflow triggers. I have tried the method below

{
  "ancestorId": "651ac8c22d125523eb7dc91d",
  "signature": "651aede5d9015982931c52bf",
  "parameters": [
    {
      "discriminator": "WorkflowComputedItemAttributeWebModel",
      "attributeCode": "attributes_tasksTargetTime",
      "value": {
        "discriminator": "WorkflowSyntaxNodeScriptWebModel",
        "script": "return raiseddatetime.AddDays(14);",
        "returnOptions": null
      }
    }
  ],
  "variables": [
    {
      "name": "raiseddatetime",
      "value": {
        "discriminator": "WorkflowSyntaxNodeInputWebModel",
        "inputParent": 1,
        "itemValue": {
          "discriminator": "WorkflowSyntaxArgumentItemValueAttributeWebModel",
          "attributeCode": "attributes_tasksRaisedTime"
        }
      }
    }
  ],
  "actionDesignCode": "designs_workflowEditItemAction"
}

But receive the following error:

 "message": "Action failed",
            "error": {
                "category": "WorkflowScriptCompilationFailed",
                "errorCode": "E1648733619",
                "errorData": {
                    "causes": [
                        {
                            "message": "AlloyBadRequestException: WorkflowScriptCompilationFailed: E1590072575: Script sandbox failed to compile",
                            "errorData": {
                                "errors": [
                                    {
                                        "failedCode": "AddDays",
                                        "location": {
                                            "start": 211,
                                            "end": 218,
                                            "length": 7,
                                            "isEmpty": false
                                        },
                                        "error": "'DateTime?' does not contain a definition for 'AddDays' and no accessible extension method 'AddDays' accepting a first argument of type 'DateTime?' could be found (are you missing a using directive or an assembly reference?)",
                                        "errorId": "CS1061"
                                    }
                                ]
                            }
                        }
                    ]
                },
                "httpStatusCode": 400,
                "message": "AlloyBadRequestException: WorkflowScriptCompilationFailed: E1590072575: Script sandbox failed to compile\nAlloyException received from RPC call"
            },

Are there any helper functions available to calculate datetime differences?

2

I found out that I needed the value of the DateTime Item.

DateTime CalcDate = raiseddatetime.Value.AddDays(14); return CalcDate;