ASP.NET Web API 2使用Get方法從表中的多個參數搜索數據

Question

這是一個代碼。 我想要ID值是12位還是13位搜索，如果數據匹配則返回對象值，如果不匹配則返回null。

public MobilinkN get(ulong ID)
{
    SubInfoNEntities robject = new SubInfoNEntities();
    using (SubInfoNEntities entities = new SubInfoNEntities())
    {
        string scnic = ID.ToString();
        if (scnic.Length == 13)
        {
            return entities.MobilinkNs.FirstOrDefault(e => e.CNIC == scnic);
        }
        else if(scnic.Length == 12)
        { 
           return entities.MobilinkNs.FirstOrDefault(e => e.MSISDN ==scnic);
        }
        return entities.MobilinkNs.FirstOrDefault(e => e.MSISDN == scnic);

    }
}

Answer 1

public MobilinkN get(ulong ID)
    {
        SubInfoNEntities robject = new SubInfoNEntities();
        using (SubInfoNEntities entities = new SubInfoNEntities())
        {
            string scnic = ID.ToString();
            if (scnic.Length == 13)
            {
                return entities.MobilinkNs.FirstOrDefault(e => e.CNIC == scnic);
            }
            else if(scnic.Length == 12)
            { 
               return entities.MobilinkNs.FirstOrDefault(e => e.MSISDN ==scnic);
            }
            else
            {
               return null;
            }
           // return entities.MobilinkNs.FirstOrDefault(e => e.MSISDN == scnic);  --> Remove this line

        }
    }