Learn how to wrap existing event sources, including tasks, asynchronous methods, .NET events, etc. in observable sequences.

“Saving changes is not permitted. The changes you have made require the following tables to be dropped and re-created. You have either made changes to a table that can’t be re-created or enabled the option Prevent saving changes that require the table to be re-created.”

To avoid this warning message, go to the “tools” menu, then click “Options”

Click on the “Designer” node

Then  uncheck the “Prevent saving changes that require table re-creation” checkbox

And you are done, the message box will not appears anymore

my extension method

public static SPFolder GetParentFolder(this SPListItem spListItem)

{

if (spListItem == null)

return null;

SPFile spFile = spListItem.Web.GetFile(spListItem.Url);

if (spFile == null)

return null;

return spFile.ParentFolder;

}

Use

SPFolder parentFolder = sPListItem.GetParentFolder();

if (parentFolder != null)

{

// do some stuffs..

}