Comment stocker les résultats renvoyés par SqlDataReader?

Question

Je suis une recrue, comme indiqué par ma question, et j'utilise un lecteur de données pour trouver les lignes associées à une certaine valeur subId. J'ai utilisé une boucle while (dr.read) et imbriqué une instruction switch case avec d'autres lecteurs dans chaque cas (code ci-dessous), mais j'ai jeté l'exception "déjà un lecteur de données ouvert associé à cette commande qui doit être fermé en premier." Existe-t-il un moyen de stocker les résultats du premier lecteur de données (les lignes pertinentes où subId = x) dans un tableau ou une liste, puis de fermer ce lecteur avant d'entrer dans l'instruction switch? (Je comprends ce qu'est un tableau dans la mesure où j'imagine que cela fonctionnerait, mais je n'ai aucune idée de ce à quoi ressemblerait la syntaxe).

string viewQuery = "SELECT ProductId FROM SubmissionProducts WHERE SubmissionId =" + x; 



      using (SqlCommand viewcmd = new SqlCommand(viewQuery, editConn)) 
      { 
       SqlDataReader dr = viewcmd.ExecuteReader(); 
       while (dr.Read()) 
       { 
        switch(dr.GetInt32(0)) 
        { 
         case 1: 
          PanelEplShow.Visible = true; 
          using (SqlCommand eplviewcmd = new SqlCommand(epl, editConn)) 
          { 
           SqlDataReader epldr = eplviewcmd.ExecuteReader(); 
           epldr.Read(); 
           LblEplShowEntity.Text = epldr.GetString(0); 
           LblEplShowTotalEmpl.Text = epldr.GetInt32(1).ToString(); 
           LblEplShowCalEmpl.Text = epldr.GetInt32(2).ToString(); 
           LblEplShowMichEmpl.Text = epldr.GetInt32(3).ToString(); 
           LblEplShowNyEmpl.Text = epldr.GetInt32(4).ToString(); 
           LblEplShowNjEmpl.Text = epldr.GetInt32(5).ToString(); 
           LblEplShowPrimEx.Text = epldr.GetInt32(6).ToString(); 
           LblEplShowLim.Text = epldr.GetInt32(7).ToString(); 
           LblEplShowPrem.Text = epldr.GetInt32(8).ToString(); 
           LblEplShowWage.Text = epldr.GetInt32(9).ToString(); 
           LblEplShowInvestCost.Text = epldr.GetInt32(10).ToString(); 
           epldr.Close(); 
          } 
          break; 
         case 2: 
          PanelProfShow.Visible = true; 
          using (SqlCommand profcmd1 = new SqlCommand(prof, editConn)) 
          { 
           SqlDataReader profdr = profcmd1.ExecuteReader(); 
           profdr.Read(); 
           LblProfShowPrimEx.Text = profdr.GetInt32(0).ToString(); 
           LblProfShowType.Text = profdr.GetInt32(1).ToString(); 
           LblProfShowLim.Text = profdr.GetInt32(2).ToString(); 
           LblProfShowRetention.Text = profdr.GetInt32(3).ToString(); 
           LblProfShowAtt.Text = profdr.GetInt32(4).ToString(); 
           LblProfShowPrem.Text = profdr.GetInt32(5).ToString(); 
           LblProfShowSublim.Text = profdr.GetInt32(5).ToString(); 
           LblProfShowEntity.Text = profdr.GetInt32(6).ToString(); 
           profdr.Close(); 
          } 
          break; 
         case 3: 
          PanelCrimeShow.Visible = true; 
          using (SqlCommand crimcmd = new SqlCommand(crim, editConn)) 
          { 
           SqlDataReader crimdr = crimcmd.ExecuteReader(); 
           crimdr.Read(); 
           LblCrimeShowEntity.Text = crimdr.GetString(0); 
           LblCrimeShowEmpl.Text = crimdr.GetInt32(1).ToString(); 
           LblCrimeShowPrimEx.Text = crimdr.GetInt32(2).ToString(); 
           LblCrimeShowLimA.Text = crimdr.GetInt32(3).ToString(); 
           LblCrimeShowDedA.Text = crimdr.GetInt32(4).ToString(); 
           LblCrimeShowPremA.Text = crimdr.GetInt32(5).ToString(); 
           LblCrimeShowLimB.Text = crimdr.GetInt32(6).ToString(); 
           LblCrimeShowDedB.Text = crimdr.GetInt32(7).ToString(); 
           LblCrimeShowPremB.Text = crimdr.GetInt32(8).ToString(); 
           crimdr.Close(); 
          } 
          break; 
         case 4: 
          PanelFidShow.Visible = true; 
          using (SqlCommand fidcmd = new SqlCommand(fid, editConn)) 
          { 
           SqlDataReader fiddr = fidcmd.ExecuteReader(); 
           fiddr.Read(); 
           LblFidShowEntity.Text = fiddr.GetString(0); 
           LblFidShowPrimEx.Text = fiddr.GetInt32(1).ToString(); 
           LblFidShowLim.Text = fiddr.GetInt32(2).ToString(); 
           LblFidShowSir.Text = fiddr.GetInt32(3).ToString(); 
           LblFidShowAtt.Text = fiddr.GetInt32(4).ToString(); 
           LblFidShowPrem.Text = fiddr.GetInt32(5).ToString(); 
           LblFidShowSublim.Text = fiddr.GetInt32(6).ToString(); 
           fiddr.Close(); 
          } 
          break; 
         case 5: 
          PanelNotShow.Visible = true; 
          using (SqlCommand notcmd = new SqlCommand(not, editConn)) 
          { 
           SqlDataReader notdr = notcmd.ExecuteReader(); 
           notdr.Read(); 
           LblNotShowPrimEx.Text = notdr.GetInt32(0).ToString(); 
           LblNotShowCov.Text = notdr.GetInt32(1).ToString(); 
           LblNotShowSharedLim.Text = notdr.GetInt32(2).ToString(); 
           LblNotShowTradLim.Text = notdr.GetInt32(3).ToString(); 
           LblNotShowTradSir.Text = notdr.GetInt32(4).ToString(); 
           LblNotShowEplLim.Text = notdr.GetInt32(5).ToString(); 
           LblNotShowEplSir.Text = notdr.GetInt32(6).ToString(); 
           LblNotShowEplPrem.Text = notdr.GetInt32(7).ToString(); 
           LblNotShowSublim.Text = notdr.GetInt32(8).ToString(); 
           notdr.Close(); 
          } 
          break; 
         case 6: 
          PanelPrivShow.Visible = true; 
          using (SqlCommand privcmd = new SqlCommand(priv, editConn)) 
          { 
           SqlDataReader privdr = privcmd.ExecuteReader(); 
           privdr.Read(); 
           LblPrivShowPrimEx.Text = privdr.GetInt32(0).ToString(); 
           LblPrivShowSharedLim.Text = privdr.GetInt32(1).ToString(); 
           LblPrivShowTradLim.Text = privdr.GetInt32(2).ToString(); 
           LblPrivShowTradAtt.Text = privdr.GetInt32(3).ToString(); 
           LblPrivShowTradSir.Text = privdr.GetInt32(4).ToString(); 
           LblPrivShowTradPrem.Text = privdr.GetInt32(5).ToString(); 
           LblPrivShowEplLim.Text = privdr.GetInt32(6).ToString(); 
           LblPrivShowEplSir.Text = privdr.GetInt32(7).ToString(); 
           LblPrivShowEplAtt.Text = privdr.GetInt32(8).ToString(); 
           LblPrivShowEplPrem.Text = privdr.GetInt32(9).ToString(); 
           LblPrivShowEplWage.Text = privdr.GetInt32(10).ToString(); 
           LblPrivShowEplSublim.Text = privdr.GetInt32(11).ToString(); 
           LblPrivShowFidLim.Text = privdr.GetInt32(12).ToString(); 
           LblPrivShowFidSir.Text = privdr.GetInt32(13).ToString(); 
           LblPrivShowFidAtt.Text = privdr.GetInt32(14).ToString(); 
           LblPrivShowFidPrem.Text = privdr.GetInt32(15).ToString(); 
           LblPrivShowFidSublim.Text = privdr.GetInt32(16).ToString(); 
           privdr.Close(); 
          } 
          break; 
         case 7: 
          PanelPubShow.Visible = true; 
          using (SqlCommand pubcmd = new SqlCommand(pub, editConn)) 
          { 
           SqlDataReader pubdr = pubcmd.ExecuteReader(); 
           pubdr.Read(); 
           LblPubShowMark.Text = pubdr.GetInt32(0).ToString(); 
           LblPubShowTick.Text = pubdr.GetInt32(1).ToString(); 
           LblPubShowTrad.Text = pubdr.GetInt32(2).ToString(); 
           LblPubShowDic.Text = pubdr.GetInt32(3).ToString(); 
           LblPubShowLim.Text = pubdr.GetInt32(4).ToString(); 
           LblPubShowSecSir.Text = pubdr.GetInt32(5).ToString(); 
           LblPubShowAllSir.Text = pubdr.GetInt32(6).ToString(); 
           LblPubShowPrem.Text = pubdr.GetInt32(7).ToString(); 
           LblPubShowPrimEx.Text = pubdr.GetInt32(8).ToString(); 
           LblPubShowAtt.Text = pubdr.GetInt32(9).ToString(); 
           LblPubShowSublim.Text = pubdr.GetInt32(10).ToString(); 
           pubdr.Close(); 
          } 
          break; 
         default: 
          break; 
        } 
       } 
       dr.Close();` 

Answer 1

J'ai trouvé que je devais régler quelque chose dans ma chaîne de connexion . Je ne sais pas si c'est un pépin .Net ou si c'est juste un ajustement nécessaire lors de l'utilisation de lecteurs imbriqués, mais je devais ajouter MultipleActiveResultSets="true" à ma chaîne de connexion stockée. Ensuite, tout a fonctionné correctement, sans avoir besoin d'un datatable. Un grand merci à tous ceux qui ont répondu. Bien que je suis sûr que les réponses ci-dessus auraient également pu fonctionner, au cas où cette question serait utile à quelqu'un dans le futur, je poste le code complet pour montrer ce qui a fonctionné pour moi. Un mot d'avertissement: si vous êtes assez nouveau pour coder pour avoir besoin de ce message, PARAMETERISEZ vos requêtes. Ce site était un projet de formation où j'avais pour instruction d'éviter le paramétrage dans le but d'apprendre d'autres choses en premier, mais c'est primordial. Bobby tables ftw.

Voici le code.

using System; 
using System.Text; 
using System.Collections.Generic; 
using System.Linq; 
using System.Data; 
using System.Data.Sql; 
using System.Data.SqlClient; 
using System.Web; 
using System.Web.UI; 
using System.Web.UI.WebControls; 

public partial class View : System.Web.UI.Page 
{ 
    protected void Page_Load(object sender, EventArgs e) 
    { 

     string x = Request.QueryString["SubmissionId"]; 
     string connectionString = System.Configuration.ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString; 
     string editCustQuery = "SELECT CustName, SicNaic, CustCity, CustAdd, CustState, CustZip FROM Customer WHERE SubId =" + x; 
     string editBroQuery = "SELECT BroName, BroAdd, BroCity, BroState, BroZip, EntityType FROM Broker WHERE SubId =" + x; 
     string editSubQuery = "SELECT Coverage, CurrentCoverage, PrimEx, Retention, EffectiveDate, Commission, Premium, Comments FROM Submission WHERE SubmissionId =" + x; 
     string epl = "SELECT Entity, Employees, CA, MI, NY, NJ, Primex, EplLim, EplSir, Premium, Wage, Sublim FROM EPL WHERE SubmissionId =" + x; 
     string prof = "SELECT Primex, EO, Limit, Retention, Att, Prem, Sublim, Entity FROM ProfessionalEO WHERE SubmissionId =" + x; 
     string crim = "SELECT Entity, Employees, PrimEx, LimA, DedA, PremA, LimitB, DedB, PremB FROM CrimeFidelity WHERE SubmissionId =" + x; 
     string fid = "SELECT Entity, PrimEx, Limit, SIR, Att, Premium, Sublim FROM Fiduciary WHERE SubmissionId =" + x; 
     string not = "SELECT PrimEx, Coverage, SharedSepLim, TradLim, TradDoSir, EplLim, EplSir, EplPrem, EplSublim FROM NotProfit WHERE SubmissionId =" + x; 
     string priv = "SELECT Primex, SharedSepLim, TradLim, TradAtt, TradDoSir, TradPrem, EplLim, EplSir, EplAtt, EplWage, EplPrem, EplInvest, FidLim, FidSir, FidAtt, FidPrem, FidSublim FROM PrivateCompany WHERE SubmissionId =" + x; 
     string pub = "SELECT Market, Ticker, TradABC, DIC, Limit, SecuritiesSir, OtherSir, Premium, PrimEx, Att, Sublim FROM PublicDO WHERE SubmissionId =" + x; 
     using (SqlConnection editConn = new SqlConnection(connectionString)) 
     { 
      editConn.Open(); 

      using (SqlCommand CustCommand = new SqlCommand(editCustQuery, editConn)) 
      { 

       SqlDataReader dr = CustCommand.ExecuteReader(); 
       dr.Read(); 
       LblCustName.Text = dr.GetString(0); 
       LblSicNaic.Text = dr.GetString(1); 
       LblCustCity.Text = dr.GetString(2); 
       LblCustAddress.Text = dr.GetString(3); 
       LblCustState.Text = dr.GetString(4); 
       LblCustZip.Text = dr.GetInt32(5).ToString(); 
       dr.Close(); 
      } 
      using (SqlCommand BroCommand = new SqlCommand(editBroQuery, editConn)) 
      { 
       SqlDataReader dr = BroCommand.ExecuteReader(); 
       dr.Read(); 
       LblBroName.Text = dr.GetString(0); 
       LblBroAddress.Text = dr.GetString(1); 
       LblBroCity.Text = dr.GetString(2); 
       LblBroState.Text = dr.GetString(3); 
       LblBroZip.Text = dr.GetInt32(4).ToString(); 
       LblEntity.Text = dr.GetString(5); 
       dr.Close(); 
      } 
      using (SqlCommand SubCommand = new SqlCommand(editSubQuery, editConn)) 
      { 
       SqlDataReader dr = SubCommand.ExecuteReader(); 
       dr.Read(); 
       LblCoverage.Text = dr.GetInt32(0).ToString(); 
       LblCurrentCoverage.Text = dr.GetInt32(1).ToString(); 
       LblPrimEx.Text = dr.GetInt32(2).ToString(); 
       LblRetention.Text = dr.GetInt32(3).ToString(); 
       LblEffectDate.Text = dr.GetDateTime(4).ToString(); 
       LblCommission.Text = dr.GetInt32(5).ToString(); 
       LblPremium.Text = dr.GetInt32(6).ToString(); 
       LblComments.Text = dr.GetString(7); 
       dr.Close(); 
       HyperLink1.NavigateUrl = "~/ViewEdit.aspx?SubmissionId=" + x; 
      } 
       string viewQuery = "SELECT ProductId FROM SubmissionProducts WHERE SubmissionId =" + x; 

       SqlCommand viewcmd = new SqlCommand(viewQuery, editConn); 

       SqlDataReader drRows = viewcmd.ExecuteReader(); 
       while (drRows.Read()) 
        { 
         switch (drRows.GetInt32(0)) 
         { 
          case 1: 
           PanelEplShow.Visible = true; 
           using (SqlCommand eplviewcmd = new SqlCommand(epl, editConn)) 
           { 
            SqlDataReader epldr = eplviewcmd.ExecuteReader(); 
            epldr.Read(); 
            LblEplShowEntity.Text = epldr.GetString(0); 
            LblEplShowTotalEmpl.Text = epldr.GetInt32(1).ToString(); 
            LblEplShowCalEmpl.Text = epldr.GetInt32(2).ToString(); 
            LblEplShowMichEmpl.Text = epldr.GetInt32(3).ToString(); 
            LblEplShowNyEmpl.Text = epldr.GetInt32(4).ToString(); 
            LblEplShowNjEmpl.Text = epldr.GetInt32(5).ToString(); 
            LblEplShowPrimEx.Text = epldr.GetInt32(6).ToString(); 
            LblEplShowLim.Text = epldr.GetInt32(7).ToString(); 
            LblEplShowSir.Text = epldr.GetInt32(8).ToString(); 
            LblEplShowPrem.Text = epldr.GetInt32(9).ToString(); 
            LblEplShowWage.Text = epldr.GetInt32(10).ToString(); 
            LblEplShowInvestCost.Text = epldr.GetInt32(11).ToString(); 
            epldr.Close(); 
           } 
           break; 
          case 2: 
           PanelProfShow.Visible = true; 
           using (SqlCommand profcmd = new SqlCommand(prof, editConn)) 
           { 
            SqlDataReader profdr = profcmd.ExecuteReader(); 
            profdr.Read(); 
            LblProfShowPrimEx.Text = profdr.GetInt32(0).ToString(); 
            LblProfShowType.Text = profdr.GetString(1); 
            LblProfShowLim.Text = profdr.GetInt32(2).ToString(); 
            LblProfShowRetention.Text = profdr.GetInt32(3).ToString(); 
            LblProfShowAtt.Text = profdr.GetInt32(4).ToString(); 
            LblProfShowPrem.Text = profdr.GetInt32(5).ToString(); 
            LblProfShowSublim.Text = profdr.GetInt32(6).ToString(); 
            LblProfShowEntity.Text = profdr.GetString(7); 
            profdr.Close(); 
           } 
           break; 
          case 3: 
           PanelCrimeShow.Visible = true; 
           using (SqlCommand crimcmd = new SqlCommand(crim, editConn)) 
           { 
            SqlDataReader crimdr = crimcmd.ExecuteReader(); 
            crimdr.Read(); 
            LblCrimeShowEntity.Text = crimdr.GetString(0); 
            LblCrimeShowEmpl.Text = crimdr.GetInt32(1).ToString(); 
            LblCrimeShowPrimEx.Text = crimdr.GetInt32(2).ToString(); 
            LblCrimeShowLimA.Text = crimdr.GetInt32(3).ToString(); 
            LblCrimeShowDedA.Text = crimdr.GetInt32(4).ToString(); 
            LblCrimeShowPremA.Text = crimdr.GetInt32(5).ToString(); 
            LblCrimeShowLimB.Text = crimdr.GetInt32(6).ToString(); 
            LblCrimeShowDedB.Text = crimdr.GetInt32(7).ToString(); 
            LblCrimeShowPremB.Text = crimdr.GetInt32(8).ToString(); 
            crimdr.Close(); 
           } 
           break; 
          case 4: 
           PanelFidShow.Visible = true; 
           using (SqlCommand fidcmd = new SqlCommand(fid, editConn)) 
           { 
            SqlDataReader fiddr = fidcmd.ExecuteReader(); 
            fiddr.Read(); 
            LblFidShowEntity.Text = fiddr.GetString(0); 
            LblFidShowPrimEx.Text = fiddr.GetInt32(1).ToString(); 
            LblFidShowLim.Text = fiddr.GetInt32(2).ToString(); 
            LblFidShowSir.Text = fiddr.GetInt32(3).ToString(); 
            LblFidShowAtt.Text = fiddr.GetInt32(4).ToString(); 
            LblFidShowPrem.Text = fiddr.GetInt32(5).ToString(); 
            LblFidShowSublim.Text = fiddr.GetInt32(6).ToString(); 
            fiddr.Close(); 
           } 
           break; 
          case 5: 
           PanelNotShow.Visible = true; 
           using (SqlCommand notcmd = new SqlCommand(not, editConn)) 
           { 
            SqlDataReader notdr = notcmd.ExecuteReader(); 
            notdr.Read(); 
            LblNotShowPrimEx.Text = notdr.GetInt32(0).ToString(); 
            LblNotShowCov.Text = notdr.GetInt32(1).ToString(); 
            LblNotShowSharedLim.Text = notdr.GetInt32(2).ToString(); 
            LblNotShowTradLim.Text = notdr.GetInt32(3).ToString(); 
            LblNotShowTradSir.Text = notdr.GetInt32(4).ToString(); 
            LblNotShowEplLim.Text = notdr.GetInt32(5).ToString(); 
            LblNotShowEplSir.Text = notdr.GetInt32(6).ToString(); 
            LblNotShowEplPrem.Text = notdr.GetInt32(7).ToString(); 
            LblNotShowSublim.Text = notdr.GetInt32(8).ToString(); 
            notdr.Close(); 
           } 
           break; 
          case 6: 
           PanelPrivShow.Visible = true; 
           using (SqlCommand privcmd = new SqlCommand(priv, editConn)) 
           { 
            SqlDataReader privdr = privcmd.ExecuteReader(); 
            privdr.Read(); 
            LblPrivShowPrimEx.Text = privdr.GetInt32(0).ToString(); 
            LblPrivShowSharedLim.Text = privdr.GetInt32(1).ToString(); 
            LblPrivShowTradLim.Text = privdr.GetInt32(2).ToString(); 
            LblPrivShowTradAtt.Text = privdr.GetInt32(3).ToString(); 
            LblPrivShowTradSir.Text = privdr.GetInt32(4).ToString(); 
            LblPrivShowTradPrem.Text = privdr.GetInt32(5).ToString(); 
            LblPrivShowEplLim.Text = privdr.GetInt32(6).ToString(); 
            LblPrivShowEplSir.Text = privdr.GetInt32(7).ToString(); 
            LblPrivShowEplAtt.Text = privdr.GetInt32(8).ToString(); 
            LblPrivShowEplPrem.Text = privdr.GetInt32(9).ToString(); 
            LblPrivShowEplWage.Text = privdr.GetInt32(10).ToString(); 
            LblPrivShowEplSublim.Text = privdr.GetInt32(11).ToString(); 
            LblPrivShowFidLim.Text = privdr.GetInt32(12).ToString(); 
            LblPrivShowFidSir.Text = privdr.GetInt32(13).ToString(); 
            LblPrivShowFidAtt.Text = privdr.GetInt32(14).ToString(); 
            LblPrivShowFidPrem.Text = privdr.GetInt32(15).ToString(); 
            LblPrivShowFidSublim.Text = privdr.GetInt32(16).ToString(); 
            privdr.Close(); 
           } 
           break; 
          case 7: 
           PanelPubShow.Visible = true; 
           using (SqlCommand pubcmd = new SqlCommand(pub, editConn)) 
           { 
            SqlDataReader pubdr = pubcmd.ExecuteReader(); 
            pubdr.Read(); 
            LblPubShowMark.Text = pubdr.GetInt32(0).ToString(); 
            LblPubShowTick.Text = pubdr.GetInt32(1).ToString(); 
            LblPubShowTrad.Text = pubdr.GetInt32(2).ToString(); 
            LblPubShowDic.Text = pubdr.GetString(3); 
            LblPubShowLim.Text = pubdr.GetInt32(4).ToString(); 
            LblPubShowSecSir.Text = pubdr.GetInt32(5).ToString(); 
            LblPubShowAllSir.Text = pubdr.GetInt32(6).ToString(); 
            LblPubShowPrem.Text = pubdr.GetInt32(7).ToString(); 
            LblPubShowPrimEx.Text = pubdr.GetInt32(8).ToString(); 
            LblPubShowAtt.Text = pubdr.GetInt32(9).ToString(); 
            LblPubShowSublim.Text = pubdr.GetInt32(10).ToString(); 
            pubdr.Close(); 
           } 
           break; 
          default: 
           break; 
         } 
        } 
       drRows.Close(); 

     }   
    } 
} 

Answer 2

charge un DataTable à la place, ce qui est à l'intérieur d'un DataReader de toute façon persistante

Pour un DataReader vous consommez, utilisez défaussez. C'est la nature de DataReaders. Si vous voulez que les données traînent, vous utiliseriez un DataTable. Simple, mais une bonne règle.

Answer 3

Chargez-le dans un DataTable.

SqlDataReader pubdr = pubcmd.ExecuteReader(); 
DataTable dt = new DataTable(); 
dt.Load(pubdr); 

développiez les commentaires:

foreach (DataRow dr in dt.Rows) 
{ 
    LblEplShowEntity.Text = dr["FIELDNAME"].ToString(); 
    //... 
} 

Answer 4

En supposant submissionId est unique dans la table SubmissionProducts, vous n'avez pas besoin d'utiliser un lecteur de données pour la requête. Vous pouvez à la place utiliser la méthode ExecuteScalar de l'objet de commande.

Si vous souhaitez obtenir un tableau de toutes les valeurs de Collumn dans la ligne actuelle d'un DataReader vous pouvez utiliser la méthode GetValues comme ceci:

SqlDataReader reader; // assumming the data reader is already opened 
    object[] columns = new object[reader.FieldCount]; 
    reader.GetValues(columns);// columns now contains all the values from the curent row