Check Sharepoint User Role through Object Model Code

protected bool CheckUserRole()
{
bool blStatus=true;
SPSite siteCollection = null;
SPWeb topLevelSite = null;
SPList list = null;
string strRoleName = string.Empty;
try
{
siteCollection = new SPSite(System.Configuration.ConfigurationManager.AppSettings["SPDocumentLibrary"]);
topLevelSite = siteCollection.OpenWeb();
SPRoleDefinitionBindingCollection usersRoles = topLevelSite.AllRolesForCurrentUser;
//Full Control
SPRoleDefinition roleDefinition0 = topLevelSite.RoleDefinitions[0];
//Design
SPRoleDefinition roleDefinition1 = topLevelSite.RoleDefinitions[1];
//"Contribute"
SPRoleDefinition roleDefinition2 = topLevelSite.RoleDefinitions[2];
//"Read"
SPRoleDefinition roleDefinition3 = topLevelSite.RoleDefinitions[3];
//"Limited Access"
SPRoleDefinition roleDefinition4 = topLevelSite.RoleDefinitions[4];
//"View Only"
SPRoleDefinition roleDefinition5 = topLevelSite.RoleDefinitions[5];
if (usersRoles.Contains(roleDefinition0))
{
strRoleName=topLevelSite.RoleDefinitions[0].Name;
}
else if (usersRoles.Contains(roleDefinition1))
{
strRoleName=topLevelSite.RoleDefinitions[1].Name;
}
else if (usersRoles.Contains(roleDefinition2))
{
strRoleName=topLevelSite.RoleDefinitions[2].Name;
}
else if (usersRoles.Contains(roleDefinition3))
{
strRoleName=topLevelSite.RoleDefinitions[3].Name;
}
else if (usersRoles.Contains(roleDefinition4))
{
strRoleName=topLevelSite.RoleDefinitions[4].Name;
}
else if (usersRoles.Contains(roleDefinition5))
{
strRoleName=topLevelSite.RoleDefinitions[5].Name;
}
if ((strRoleName == "Read") || (strRoleName == "Limited Access") || (strRoleName == "View Only"))
{
blStatus = false;
}
else
{
blStatus = true;
}
}
catch (Exception ex)
{
Response.Write(ex.Message);
}
finally
{
topLevelSite.AllowUnsafeUpdates = false;
siteCollection.AllowUnsafeUpdates = false;
siteCollection.Dispose();
topLevelSite.Dispose();
}
return blStatus;
}