/// <summary>
/// Apply the changes
/// </summary>
/// <param name="instance"></param>
/// <param name="wfChanges"></param>
private static void ValidateAndApplyChanges(
WorkflowInstance instance, WorkflowChanges wfChanges)
{
//validate the structural changes before applying them
ValidationErrorCollection errors = wfChanges.Validate();
if (errors.Count == 0)
{
try
{
//apply the changes to the workflow instance
instance.ApplyWorkflowChanges(wfChanges);
}
catch (Exception e)
{
Console.WriteLine("Exception applying changes: {0}",
e.Message);
}
}
else
{
//the proposed changes are not valid
foreach (ValidationError error in errors)
{
Console.WriteLine(error.ToString());
}
}
}
/// <summary>
/// Add a new custom activity to this workflow instance
/// </summary>
/// <param name="instance"></param>
private void AddNewActivity()
{
//create an instance of the specified new activity
if (NewActivityType != null && NumberProperty != null)
{
//create a workflow changes object
WorkflowChanges wfChanges = new WorkflowChanges(this);
//find the SequenceActivity that is a placeholder
//for new activities
CompositeActivity placeholder
= wfChanges.TransientWorkflow.GetActivityByName(
"sequencePlaceholder") as CompositeActivity;
if (placeholder == null)
{
return;
}
//construct an instance of the activity
//using reflection
ConstructorInfo ctor
= NewActivityType.GetConstructor(Type.EmptyTypes);
Activity newActivity = ctor.Invoke(null) as Activity;
//bind the TestNumber property of the activity
//to the TestNumber property of the workflow
newActivity.SetBinding(NumberProperty,
new ActivityBind(this.Name, "TestNumber"));
//add the new custom activity to the workflow
placeholder.Activities.Add(newActivity);
//validate the structural changes before applying them
ValidationErrorCollection errors = wfChanges.Validate();
if (errors.Count == 0)
{
//apply the changes to the workflow instance
this.ApplyWorkflowChanges(wfChanges);
}
else
{
//the proposed changes are not valid
foreach (ValidationError error in errors)
{
Console.WriteLine(error.ToString());
}
}
}
}