accessing an instantiated sealed class public member

Question

i am trying to instatiate a public sealed class in my program,

the thing is, ...as i am still fresh C# .net _not-yet Developer , i find this issue a little difficult ...

As for the problem in Question, you can skip straight to Program example, or read the folowing background:

DB_Schema is a helper namespace , i've Created, to deal with the data accessing

(it holds tables And SP s names ..etc')

one of its classes(below) deals with Stored Procedures , and this one holds names of SPs Parameters

public sealed class SProc
{
    public sealed class GetCPAReport
    {
        public const string RecordNum = "@RecordNum",
                            CPAColumnName = "@CPAColumn_Name",
                            Value = "@value",
                            IsFreelance = "@isFreelance";
    }

}

• Usage in program:

within method for data access via SP

private DataTable Get_RefTable_OfUsersBy(string DepartmetID)
{
    SProc.GetCPAReport SProcGetCpa = SProc.GetCPAReport();
    SP_Params.Add(new SqlParameter(SProcGetCpa.IsFreelance, 1));
}

trying to access one of the instance ( SProcGetCpa ) members is not possible the way i tried .

i could just make class SProc + it's sub class UpdateCPAReport not sealed and ...

but as i was searching the question " can sealed class be instantiated?

well.. the answer is Yes ... though trying to find information on the error:

cannot be accessed with an instance reference; qualify it with a type name instead

yields no results, Nor an Example of Accessing Instantiated sealed class public member code atleast not for fresh .net C#arpers like me

- Update

i wanted to avoid long lines and make custom short names for the strings that represents the stored procedure name

instead of

ParListEmployeeUsrs.SP_Params.Add(new SqlParameter(HTSPs.RobTC_CPA_Users_Names_JobPosition.IsFreelance, SelectedDepartmentID));

update 2

for future comers on this subject who seeks for an answer

as suggested by a dear friend of ours, here in StackOverflow

if you do have to make a short namings for your classes, when using them for current peoject :

just place this among the using s of your project

using system...
using restOf.net
//just add your own as follows !

using shortClassName = myHelperNameSpace.MyIncrediblyUnnecessaryLongHelperClassName;

Answer 1

GetCPAReport doesn't have any instance members. const members are implicitly static. In C#, you can't access static members through a reference as you're trying to at the moment.

You just want:

SP_Params.Add(new SqlParameter(SProc.GetCPAReport.IsFreelance, 1));

Personally I'd make GetCPAReport a static class, too. There's no point in instantiating it, as it just contains constants... so actively prevent it from being instantiated.