Approve a SharePoint workflow task using SharePoint Web Services / Object Model

Question

I have created a workflow is SharePoint Designer and associated it with a list. The workflow creates an approval process, so SharePoint creates a task in the Tasks list so t

Answer 1

I'm not sure if Madhur's solution works on the associated item or on the task, but to update the task try:

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Body>
<UpdateListItems
xmlns="http://schemas.microsoft.com/sharepoint/soap/">
<listName>Tasks</listName>
<updates>
<Batch OnError="Continue" ListVersion="1">
<Method ID="1" Cmd="Update">
<Field Name="ID">199</Field>
<Field Name="Outcome">Approved</Field>
<Field Name="Status">Completed</Field>
<Field Name="ows_TaskStatus">Approved</Field>
</Method>
</Batch>
</updates>
</UpdateListItems>
</soap:Body>
</soap:Envelope>

Info on the service:

http://objectmix.com/sharepoint/800144-updatelistitems-web-service-does-not-update-field.html

Info on the approved field:

http://social.msdn.microsoft.com/Forums/en/sharepointworkflow/thread/6712d379-2df6-4223-9a29-b2e60493f1b6

http://social.msdn.microsoft.com/Forums/en/sharepointworkflow/thread/3dc95190-cc61-4067-ac35-2d1a82fad499

Answer 2

You can use the following code that uses the lists web service and the UpdateListItems method. The key is to use the Cmd='Moderate'

 public static XmlNode UpdateListItemApprove()
 {
            listservice.Lists listProxy = new listservice.Lists();


            string xml = "<Batch OnError='Continue'><Method ID='1' Cmd='Moderate'><Field Name='ID'/><Field Name='FileRef'>http://basesmcdev2/sites/tester1/approvals/KL022030.lic</Field><Field Name=\"_ModerationStatus\" >0</Field></Method></Batch>";

            XmlDocument doc = new XmlDocument();
            doc.LoadXml(xml);

            XmlNode batchNode = doc.SelectSingleNode("//Batch");

            listProxy.Url = "http://basesmcdev2/sites/tester1/_vti_bin/lists.asmx";
            listProxy.UseDefaultCredentials = true;

            XmlNode resultNode = listProxy.UpdateListItems("approvals", batchNode);

            return resultNode;


}

Answer 3

After a lot of trials and investigation I just had the following code working to approve the task

SPSite site = new SPSite("http://servername/");
using (SPWeb web = site.OpenWeb())
{
    SPList list = web.Lists["TestList"];
    SPListItem item = list.GetItemById(22);
    SPWorkflow workflow = item.Workflows[0];
    SPWorkflowTask task = workflow.Tasks[0];

    Hashtable ht = new Hashtable();             
    ht[SPBuiltInFieldId.Completed] = "TRUE";
    ht["Completed"] = "TRUE";
    ht[SPBuiltInFieldId.PercentComplete] = 1.0f;
    ht["PercentComplete"] = 1.0f;
    ht["Status"] = "Completed";
    ht[SPBuiltInFieldId.TaskStatus] = SPResource.GetString(new CultureInfo((int)task.Web.Language, false), Strings.WorkflowStatusCompleted, new object[0]);
    ht[SPBuiltInFieldId.WorkflowOutcome] = "Approved";
    ht["TaskStatus"] = "Approved";
    ht["FormData"] = SPWorkflowStatus.Completed;

    web.AllowUnsafeUpdates = true;
    SPWorkflowTask.AlterTask((task as SPListItem), ht, true);
}

I suspect that ht["TaskStatus"] = "Approved"; is that attribute that solved it. Anyway I will try to narrow on the set of properties that need to be changed.