Manage Item Level Permissions Programmatically

Many times we are into a situation like we need to manage the Item Level Permissions programmatically.

Below is the code snippet by which we can manage Item Level Permissions programmatically.

            SPSite objSPSite = new SPSite("<Site URL>");

            SPWeb objSPWeb = objSPSite.OpenWeb();

            SPList oSPList = objSPWeb.Lists["<List NAme>"];

            //Create new user to grant access

            /***************************/

            SPUserCollection users = objSPWeb.Users;

            SPUser CurrentUser = users[@"SHAREPOINT\system"];

            /***************************/

             

            foreach (SPListItem objSPListItem in oSPList.Items)

            {

                //Remove all Permissions

                RemoveAllPermissions(objSPListItem);

                //Grant permissions to List Items

                AddNewPermission(objSPListItem, objSPWeb, SPRoleType.Contributor, CurrentUser);

            }

/*************************************************************************/

Function to remove all Permissions from a List Item

private static void RemoveAllPermissions(SPListItem CurrentlistItem)

        {

            CurrentlistItem.BreakRoleInheritance(true);

            SPRoleAssignmentCollection objSPRoleAssColn = CurrentlistItem.RoleAssignments;

            for (int i = objSPRoleAssColn.Count - 1; i >=0 ; i--)

            {

                objSPRoleAssColn.Remove(i);

            }          

        }

/*************************************************************************/

Function To add new permission to a List Item

       

        private static void AddNewPermission(SPListItem ListItem, SPWeb objSPWeb, SPRoleType objSPRoleType, SPPrincipal objSPPrincipal)

        {

            SPRoleDefinition objSPRoleDefinition = objSPWeb.RoleDefinitions.GetByType(objSPRoleType);

            SPRoleAssignment objSPRoleAssignment = new SPRoleAssignment(objSPPrincipal);

            objSPRoleAssignment.RoleDefinitionBindings.Add(objSPRoleDefinition);

            ListItem.RoleAssignments.Add(objSPRoleAssignment);

            ListItem.Update();

        }

    }