sharepoint 读取权限操作

using (SPSite oSite = new SPSite("http://localhost"))
{
using (SPWeb oWeb = oSite.RootWeb)
{
SPList oList = oWeb.Lists[""];
SPRoleAssignmentCollection def = oList.RoleAssignments;
foreach (SPRoleAssignment r in def)
{
SPPrincipal p = r.Member;
Console.Write(p.Name+":");
foreach (SPRoleDefinition roleDef in r.RoleDefinitionBindings)
{
Console.Write(roleDef.Name);
Console.Write("/n");
}
}
Console.ReadLine();
}
}