remove all permissions from a list item using workflow

Question

I am creating a workflow that removes permissions from a list item then adds a new set of permissions. I know how to add the permissions. but I was wondering with removing the permissions is there an easy way to remove all the permissions from the list, or do you have to go through every group and user and tell the workflow to remove them. this is sharepoint 2010

Answer 1

Adding comment as answer

Using impersonation step, there is a way to break inheritance and remove all the permissions. Check: Using item level permissions. Specifically, replace permissions action will do the job.

Answer 2

If you have to customize the permissions on item level, while on added and updated events you have to remove all permissions (except for author), then grant permission for each user as you want to assign. Suppose, i am taking example of Assigned Users, Everyone and Author itself. Just go through the code here, you will get idea.

private static void GrantPermission(string EveryonePermission, SPListItem CurrentListItem, SPWeb oSPWeb, string[] assignedUsersArray)
    {

        var fullUserName = CurrentListItem[SPBuiltInFieldId.Author] as string;
        var userName = fullUserName.Split('#')[1];
        SPUser Author = oSPWeb.EnsureUser(userName);

        SPUser currentUser = oSPWeb.CurrentUser;

        RemoveAllPermissions(CurrentListItem, currentUser);

        SPUser allUsers = oSPWeb.AllUsers[@"c:0(.s|true"];   // for everyone
        SPRoleDefinitionCollection roleCollection = oSPWeb.RoleDefinitions;

        SPRoleDefinition EveryOneDefinition = roleCollection[EveryonePermission]; // for everyone
        SPRoleDefinition roleContribute = roleCollection["Full Control"];// for assigned user and for author

        SPRoleAssignment oSPRoleAssignmentAuthor = new SPRoleAssignment(Author);// for author
        SPRoleAssignment roleAssignment = new SPRoleAssignment((SPPrincipal)allUsers);// for everyone
        if (assignedUsersArray.Length > 1)
        {
            for (int i = 0; i < assignedUsersArray.Length; i++)
            {
                if (assignedUsersArray[i] != null)
                {
                    SPUser assignedUser = oSPWeb.EnsureUser(assignedUsersArray[i]);
                    SPRoleAssignment oSPRoleAssignment = new SPRoleAssignment(assignedUser);// for assigned user
                    oSPRoleAssignment.RoleDefinitionBindings.Add(roleContribute);// for assigned user
                    CurrentListItem.RoleAssignments.Add(oSPRoleAssignment);
                }

            }
        }
        oSPRoleAssignmentAuthor.RoleDefinitionBindings.Add(roleContribute);// for author
        roleAssignment.RoleDefinitionBindings.Add(EveryOneDefinition);// for everyone
        CurrentListItem.RoleAssignments.Add(oSPRoleAssignmentAuthor);
        CurrentListItem.RoleAssignments.Add(roleAssignment);
        CurrentListItem.Update();
    }

    private static void RemoveAllPermissions(SPListItem CurrentlistItem,SPUser currentUser)
    {
        SPSecurity.RunWithElevatedPrivileges(delegate()
                {
                    //The below function Breaks the role assignment inheritance for the list and gives the current list its own copy of the role assignments
                    CurrentlistItem.BreakRoleInheritance(true);
                    //Get the list of Role Assignments to list item and remove one by one.
                    SPRoleAssignmentCollection SPRoleAssColn = CurrentlistItem.RoleAssignments;
                    for (int i = SPRoleAssColn.Count - 1; i >= 0; i--)
                    {

                        string str = SPRoleAssColn.ToString();
                        if (SPRoleAssColn[i].Member.ToString() == currentUser.ToString())
                        {
                        }
                        else
                        {
                            SPRoleAssColn.Remove(i);
                        }

                    }

                });
    }