读多行数据使用SqlDataReader的

我有下面的SQL语句如下：读多行数据使用SqlDataReader的

SELECT * FROM ViewSectorInvestments WHERE AccountNumber = @AccountNumber

字段中ViewSectorInvestments：

AccountNumber 
SectorName 
AmountInvested

我试图计算AmountInvested反对每个扇区总投资。所以公式为：AmountInvested/TotalInvestments * 100

我的代码如下：

string DMConnectionString = ConfigurationManager.ConnectionStrings["DMConnectionString"].ConnectionString; 
    SqlConnection DMConnection = new SqlConnection(DMConnectionString); 
    DMConnection.ConnectionString = DMConnectionString; 

    string DMCommandText = "SELECT Name,RiskProfile,AccountNumber,TotalInvestments FROM ViewClientDetails WHERE AccountNumber = @AccountNumber; SELECT * FROM ViewSectorInvestments WHERE AccountNumber = @AccountNumber ;SELECT * FROM ViewStockTypeInvestments WHERE AccountNumber = @AccountNumber "; 
    SqlCommand DMCommand = new SqlCommand(DMCommandText, DMConnection); 
    DMCommand.Parameters.AddWithValue("@AccountNumber", lb_AcctNum.Text); 
    DMConnection.Open(); 

    SqlDataReader DMReader = DMCommand.ExecuteReader(); 

    ArrayList SectorArray = new ArrayList(); 
    ArrayList StockTypeArray = new ArrayList(); 

    while (DMReader.Read()) 
    { 
     CustName.Text = DMReader["Name"].ToString(); 
     lb_Risk.Text = DMReader["RiskProfile"].ToString(); 
     T_Investment.Text = DMReader.GetDecimal(DMReader.GetOrdinal("TotalInvestments")).ToString("N2"); 
     Client_RiskProfile.Text = DMReader["RiskProfile"].ToString(); 

     //encounter error when i add the datas into arraylist. 
     //System.IndexOutOfRangeException: SectorName 

     SectorArray.Add(DMReader.GetOrdinal("SectorName").ToString()); 
     StockTypeArray.Add(DMReader.GetOrdinal("BlueChipName").ToString()); 


     foreach(Object objReader in SectorArray){ 
     //compute the percentage of amount invested in each sector 
     //check if the percentage is more than 25% 
     //if it is more than 25% lbMsg (an label) shows the name of the sector. 

     } 
    } 

    DMReader.Close(); 
    DMConnection.Close(); 
}

当我考出来的SQL语句：

SELECT * FROM ViewSectorInvestments WHERE AccountNumber = @AccountNumber

我得到的结果是：

AccountNumber SectorName    AmountInvested 
1001   Commerce   97230.00000 
1001   Construction   389350.00000 
1001   Finance    222830.00000 
1001   Hotel      14910.00000 
1001   Loans      105070.00000 
1001   Manufacturing   1232210.00000 
1001   Mining/Quarrying  32700.00000

我遇到System.IndexOutOfRangeException：Secto RNAME。我的代码有什么问题？请指教我。提前致谢。

来源

2012-02-02 user1125911

这里有问题吗？反正很难找到。我建议不要把你的问题的症结放在你的代码块的评论中。 – pseudocoder 2012-02-02 18:33:53

另外，您没有任何代码尝试计算，甚至没有从查询结果中提取计算变量，而且您似乎也不了解SqlDataReader如何工作。你是否正在使用别人的代码而没有任何经验？ – pseudocoder 2012-02-02 18:45:31

我还没有添加计算代码。我甚至不能读现在的价值。 – user1125911 2012-02-02 18:46:59

string DMCommandText = "SELECT Name,RiskProfile,AccountNumber,TotalInvestments FROM ViewClientDetails WHERE AccountNumber = @AccountNumber; SELECT * FROM ViewSectorInvestments WHERE AccountNumber = @AccountNumber ;SELECT * FROM ViewStockTypeInvestments WHERE AccountNumber = @AccountNumber ";

这CommandText中包含多个查询。只有最后一个SELECT语句的结果才会返回到SqlDataReader。

SectorArray.Add(DMReader.GetOrdinal("SectorName").ToString());

您试图访问你的SqlDataReader的名为“SectorName”字段的列序号。导致异常的问题可能是该列不存在，但很难说，因为您在CommandText中使用了SELECT *。

来源

2012-02-02 18:55:00 pseudocoder

那么这意味着我不能有多个选择语句？ – user1125911 2012-02-02 19:02:00

读多行数据使用SqlDataReader的

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