SharePoint 判断用户在文件夹上是否有权限的方法

public
static bool UserInItemExists(SPWeb web, SPListItem item,
string strUserLoginName){
bool boolResult = false;
try { if (item !=
null) { SPRoleAssignmentCollection roles = item.RoleAssignments;
foreach (SPRoleAssignment role
in roles) { sbResult.Append(role.Member.Name.ToUpper().Trim()); SPUser loginuser =
null; try { loginuser =
new SPSite(SPContext.Current.Site.Url).RootWeb.Users[strUserLoginName]; }
catch { loginuser =
null; } SPUser memberuser =
null; try { memberuser = ((Microsoft.SharePoint.SPUser)(role.Member)); }
catch { memberuser =
null; }
if (loginuser != null && memberuser !=
null) { if (loginuser.Sid == memberuser.Sid) { boolResult =
true;
break; } } } } }
catch { } return boolResult;}