When working with Task Schedule Service you might get following exception when invoking BeginDeletTask:
ArgumentException: Value Cannot be null.
This exception is thrown by executing of following code:
| protected void Button2_Click(object sender, EventArgs e)
{
DistributedTask task = getTask(); TaskSchedulerClient client = ServiceReferences.CreateImport1("Tasks");
IAsyncResult asyncResult = client.BeginDeleteTask(task, cb => { }, null);
client.EndDeleteTask(asyncResult);
}
private DistributedTask getTask()
{
TaskSchedulerClient client = ServiceReferences.CreateImport1("Tasks");
IAsyncResult asyncResultAllTasks = client.BeginGetAllTasks(cb =>
{
Debug.WriteLine("");
}, null);
ReadOnlyCollection<DistributedTask> tasks = client.EndGetAllTasks(asyncResultAllTasks);
return tasks.Count > 0 ? tasks[0] : null;
} |
To workaround this issue, insert the yellow line in the code which stops distributed the task.:
| protected void Button2_Click(object sender, EventArgs e)
{
DistributedTask task = getTask();
TaskSchedulerClient client = ServiceReferences.CreateImport1("Tasks"); task.SelfLink = new Uri(client.EndpointAddress.AbsoluteUri);
IAsyncResult asyncResult = client.BeginDeleteTask(task, cb => { }, null); client.EndDeleteTask(asyncResult);
}
|
Posted
Sep 03 2011, 04:27 PM
by
Damir Dobric