Using OutArgument in Definition of another Activity - workflow-foundation-4

Question

I'm creating a Workflow that can call a custom activity called post that will do a webrequest and return the response as an xmldoc. I tried to return dynamic but that didn't work. I then want to take a specific value in the xml doc and add it into the post dada of the next post call to chain calls together. What I can't figure out is how to get the response data from the first post into the post data of the second post. Any help would be greatly appreciated.
Variable<XmlDocument> output1 = new Variable<XmlDocument>();
ActivityBuilder ab1 = new ActivityBuilder();
ab1.Name = "CustomWorkflow";
ab1.Implementation = new Sequence
{
Activities =
{
new Post()
{
PostData =
"<xml></xml>",
EndPoint =
"www.test.com",
ContentType = "text/xml;charset=\"utf-8\"",
Accept = "text/xml",
Headers = "SOAPAction,Test",
Response = new OutArgument<XmlDocument>(output1)
},
new Post()
{
PostData =
"<xml>"+ output1.GetSingleNode("stuff here") "</xml>",
EndPoint =
"www.test.com",
ContentType = "text/xml;charset=\"utf-8\"",
Accept = "text/xml",
Headers = "SOAPAction,Test"
}
},
Variables =
{
output1
}
};

Answer 1

think you are asking: How do I transfer a value from 1 Activity to another.
If so, there are a couple of ways to do this.
1)
Have a variable at the workflow level that takes the output from your first activity and then pass this variable as an input parameter to the next activity.
2)
Have a variable that is a data structure and pass the structure into all your activities in sequence. In each activity you can add/edit/delete data in the structure and because a workflow variable is a reference variable then this data is available to the next activity is the sequence once you pass in the data object.
Instead of a variable you can use an Argument if you want to pass initial data into the workflow. From then on Arguments behaves like Variables