工作流在活动之间传递价值

Question

I have a CodeActivity GetEstimatedArrivalTime that gets a datetime and returns it as an out argument.

In the designer view, how can I take this value input it into the sequence diagram?

public sealed class CodeActivityGetEVA : CodeActivity
{
    public InArgument<int> EventID { get; set; }
    public OutArgument<DateTime> EVA {get;set;}

    protected override void Execute(CodeActivityContext context)
    {
        EVA.Set(context, DateTime.Now);
    }

Answer 1

Initialize a variable at sequence level (lets call it "EstimatedArrivalTimeVar") and attach it to CodeActivityGetEVA 's EVA out argument. From then on you can use EstimatedArrivalTimeVar with the value assigned to it.

Note that you can use a CodeActivity with a TResult as an out argument already available:

public sealed class CodeActivityGetEVA : CodeActivity<DateTime>
{
    public InArgument<int> EventID { get; set; }

    protected override DateTime Execute(CodeActivityContext context)
    {
        return DateTime.Now;
    }
}