var propDefInfos =
connection.WebServiceManager.PropertyService.GetPropertyDefinitionInfosByEntityClassId("FILE", null);
var result =
propDefInfos.Where(prof => prof.PropDef.SysName == "CheckoutDate").First();
File[] files =
connection.WebServiceManager.DocumentService.GetLatestFilesByFolderId(selection.Id, false);
foreach (File qw in files)
{
if (qw.CheckedOut)
{
var value = connection.WebServiceManager.PropertyService.GetProperties("FILE",
new long[] { qw.Id }, new long[] { result.PropDef.Id }).First();
System.Windows.Forms.MessageBox.Show(qw.CkInDate + " CkInDate\n " +
qw.CreateDate + " CreateDate\n " +
qw.ModDate + " ModDate\n " +
value.Val + " CheckoutDate");
}
}