Update Field mithilfe des Liste-Webservices

private static Lists InitListsService(string url, bool usedefaultCredentials) 

{

  Lists Lists = new Lists(); Lists.Url = url + "/_vti_bin/Lists.asmx";

  Lists.UseDefaultCredentials = usedefaultCredentials; 

  if (usedefaultCredentials) 

  {

    string user = ConfigurationSettings.AppSettings["user"]; 

    string passwd = ConfigurationSettings.AppSettings["passwd"]; 

    string domain =  ConfigurationSettings.AppSettings["domain"]; 

    Lists.Credentials = new System.Net.NetworkCredential(user, passwd, domain);

  } 

  return Lists;

}

XmlDocument xmlDoc = new System.Xml.XmlDocument();

XmlNode ndUpdateFields = xmlDoc.CreateNode(XmlNodeType.Element, "Fields", ""); StringBuilder methods = new StringBuilder(); methods.Append(""); methods.Append(");

methods.Append("ShowInDisplayForm='FALSE' "); methods.Append("Type='Number' "); methods.Append("Name='fieldname' "); methods.Append("DisplayName='internalname' "); 

methods.Append("Required='FALSE' "); methods.Append("FromBaseType='TRUE' "); methods.Append("Description=''/>"); methods.Append("");

ndUpdateFields.InnerXml = methods.ToString(); 

XmlNode xReturn = lists.UpdateList("ListName", null, null, ndUpdateFields, null, null);