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While loop

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Join Date: Aug 2008

Posts: 94

Reputation: Tank50 is an unknown quantity at this point

Solved Threads: 1

Tank50

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Junior Poster in Training

While loop

Mar 26th, 2009

Hi guys

I have a problem in my project.Below I mention the coding I wrote it for testing purpose.
In below coding the second while loop never run,only

Help with Code Tags

(Toggle Plain Text)

            SqlDataReader reader = DbCon.Get_Invoices();
            int x = 0;
            while (reader.Read())
            {
                x++;                                                  1
             }
           MessageBox.Show(x.ToString());

           chart2.DataBindCrossTable(reader, "ExecutiveCode", "Date1", "Total", "");

           foreach (Series series in chart2.Series)
           {
               series.ChartType = SeriesChartType.Line;
           }
           chart2.ResetAutoValues();
           DataSet ds = new DataSet();
           DataTable dt = ds.Tables.Add("tbldata");
           int intIdx = 0;


           for (int i = 0; i < reader.FieldCount; i++)
           {
      dt.Columns.Add(reader.GetName(i), reader.GetFieldTypei));
           }

           while (reader.Read())
           {                                                      2
               x++;     }                                   
           MessageBox.Show(x.ToString());

         while (reader.Read())
          {                                                    3
          
          MessageBox.Show("test");
           DataRow r = dt.NewRow();
           if (intIdx >= intSkip)
           {
            for (int i = 0; i < reader.FieldCount; i++)
            {
          r[i] = reader[i];                                                                                
            }
      dt.Rows.Add(r);
         }

In above coding 3rd while loop never runs and it never give me Meassage I expected.1 and 2 while loop work and I generate the x value also.Please tell me y that 3rd loop never work

Thanks
Tank50

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Join Date: Oct 2006

Posts: 89

Reputation: TylerSBreton is an unknown quantity at this point

Solved Threads: 3

TylerSBreton TylerSBreton is offline

Offline

Junior Poster in Training

Re: While loop

Mar 26th, 2009

•

Originally Posted by Tank50

Hi guys

I have a problem in my project.Below I mention the coding I wrote it for testing purpose.
In below coding the second while loop never run,only
Help with Code Tags

(Toggle Plain Text)
            SqlDataReader reader = DbCon.Get_Invoices();
            int x = 0;
            while (reader.Read())
            {
                x++;                                                  1
             }
           MessageBox.Show(x.ToString());

           chart2.DataBindCrossTable(reader, "ExecutiveCode", "Date1", "Total", "");

           foreach (Series series in chart2.Series)
           {
               series.ChartType = SeriesChartType.Line;
           }
           chart2.ResetAutoValues();
           DataSet ds = new DataSet();
           DataTable dt = ds.Tables.Add("tbldata");
           int intIdx = 0;


           for (int i = 0; i < reader.FieldCount; i++)
           {
      dt.Columns.Add(reader.GetName(i), reader.GetFieldTypei));
           }

           while (reader.Read())
           {                                                      2
               x++;     }                                   
           MessageBox.Show(x.ToString());

         while (reader.Read())
          {                                                    3
          
          MessageBox.Show("test");
           DataRow r = dt.NewRow();
           if (intIdx >= intSkip)
           {
            for (int i = 0; i < reader.FieldCount; i++)
            {
          r[i] = reader[i];                                                                                
            }
      dt.Rows.Add(r);
         }
SqlDataReader reader = DbCon.Get_Invoices(); int x = 0; while (reader.Read()) { x++; 1 } MessageBox.Show(x.ToString()); chart2.DataBindCrossTable(reader, "ExecutiveCode", "Date1", "Total", ""); foreach (Series series in chart2.Series) { series.ChartType = SeriesChartType.Line; } chart2.ResetAutoValues(); DataSet ds = new DataSet(); DataTable dt = ds.Tables.Add("tbldata"); int intIdx = 0; for (int i = 0; i < reader.FieldCount; i++) { dt.Columns.Add(reader.GetName(i), reader.GetFieldTypei)); } while (reader.Read()) { 2 x++; } MessageBox.Show(x.ToString()); while (reader.Read()) { 3 MessageBox.Show("test"); DataRow r = dt.NewRow(); if (intIdx >= intSkip) { for (int i = 0; i < reader.FieldCount; i++) { r[i] = reader[i]; } dt.Rows.Add(r); }
In above coding 3rd while loop never runs and it never give me Meassage I expected.1 and 2 while loop work and I generate the x value also.Please tell me y that 3rd loop never work

Thanks
Tank50

Reader has reached the end after the first while loop, and the "context" of it is basically EOF. Neither your second or third loop run. The only reason you think your second loop runs is because it is printing the correct value for x outside of the loop, which was calculated in the first loop. Try resetting reader before each loop.