These activities model primitive operations that exist in almost every programming environment, such as conditional branching, looping, and grouping of sub-activities. We will start with an activity that appears many times in these code samples, the CodeActivity.
The Code activity's only interesting feature is its ExecuteCode event. We will need to pair the event with an event handler before the activity will pass validation. In the workflow designer, we can double-click on a Code activity, and Visual Studio will create and assign the event handler for us — all we need to do is write the code. The following code is an event handler for ExecuteCode that displays a message on the screen.
private void codeActivity1_ExecuteCode(object sender, EventArgs e)
{
Console.WriteLine("Hello, world!");
}
The screenshot below shows a Code activity as it appears in the designer. A red exclamation point hovers above the top right of the activity because we have not assigned an...