CMIS-464: CheckIn without properties fails

git-svn-id: https://svn.apache.org/repos/asf/chemistry/dotcmis/trunk@1196311 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/DotCMIS/binding/atompub/atompub-writer.cs b/DotCMIS/binding/atompub/atompub-writer.cs
index 05b99d7..7e03749 100644
--- a/DotCMIS/binding/atompub/atompub-writer.cs
+++ b/DotCMIS/binding/atompub/atompub-writer.cs
@@ -145,14 +145,17 @@
         {

             string result = "";

 

-            foreach (cmisProperty property in cmisObject.properties.Items)

+            if (cmisObject.properties != null && cmisObject.properties.Items != null)

             {

-                if (PropertyIds.Name == property.propertyDefinitionId && property is cmisPropertyString)

+                foreach (cmisProperty property in cmisObject.properties.Items)

                 {

-                    string[] values = ((cmisPropertyString)property).value;

-                    if (values != null && values.Length > 0)

+                    if (PropertyIds.Name == property.propertyDefinitionId && property is cmisPropertyString)

                     {

-                        return values[0];

+                        string[] values = ((cmisPropertyString)property).value;

+                        if (values != null && values.Length > 0)

+                        {

+                            return values[0];

+                        }

                     }

                 }

             }