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I am making desktop application using C#.I have created a form in which there are various labels with respective textboxes,combox(like threshold id,name,date etc) and one listbox.I have taken 2 buttons add ,update for a form.I have taken group box in which there is a list box with 2 buttons add.delete.For a whole form it add/update the contents(like id,name,date and items of listbox(for each entry items in listbox vary).Now group box containing listbox,add/update button operate accordingly for each entry made for threshold id,name,date etc.the problem is when i add whole contents of the form .I get an error

"Unable to cast object to type 'System.Data.DataRowView' to type 'System.String'.
I have checked when i dont include listbox coding ,there is no error and when i include listbox coding i get an error
below is the coding

 private void btmadd_Click(object sender, EventArgs e)
          SqlConnection con = new SqlConnection("Data Source=SW-PC-20;Integrated security =SSPI;Initial catalog=PSM");
          SqlCommand cmd = new SqlCommand("INSERT INTO" +
           " Publicity_Threshold(Threshold_id,Threshold_Name,Media_method_ID,Media_Used,Starting_Date,Ending_Date,Duration_Tenure,State,City,Area,Target_Audience,Target_Audience_Volume,Walkins_Volume,Person_Incharge,Budget,Quantum_of_Threshold,Resources)" +
            " VALUES" +
           " (@Threshold_id,@Threshold_Name,@Media_method_ID,@Media_Used,@Starting_Date,@Ending_Date,@Duration_Tenure,@State,@City,@Area,@Target_Audience,@Target_Audience_Volume,@Walkins_Volume,@Person_Incharge,@Budget,@Quantum_of_Threshold,@Resources)", con);
          cmd.Parameters.Add(new SqlParameter("@Threshold_id", Convert.ToInt32(txtThresholdID.Text)));
          cmd.Parameters.Add(new SqlParameter("@Threshold_Name", cboThreholdname.Text));
          cmd.Parameters.Add(new SqlParameter("@Media_method_ID", Convert.ToInt32(cbomethodid.Text)));
          cmd.Parameters.Add(new SqlParameter("@Media_Used", cbomediaused.Text));
          cmd.Parameters.Add(new SqlParameter("@Starting_Date", this.startingdate.Value));
          cmd.Parameters.Add(new SqlParameter("@Ending_Date", this.endingdate.Value));
          cmd.Parameters.Add(new SqlParameter("@Duration_Tenure", txtduration.Text));
          cmd.Parameters.Add(new SqlParameter("@State", cboState.Text));
          cmd.Parameters.Add(new SqlParameter("@City", cboCity.Text));
          cmd.Parameters.Add(new SqlParameter("@Area", cboArea.Text));
          cmd.Parameters.Add(new SqlParameter("@Target_Audience", cboTargetAudience.Text));
          cmd.Parameters.Add(new SqlParameter("@Target_Audience_Volume", Convert.ToInt32(txtaudiencevolume.Text)));
          cmd.Parameters.Add(new SqlParameter("@Walkins_Volume", Convert.ToInt32(txtinquiryvolume.Text)));
          cmd.Parameters.Add(new SqlParameter("@Person_Incharge", txtperson.Text));
          cmd.Parameters.Add(new SqlParameter("@Budget", Convert.ToInt32(txtBudget.Text)));
          cmd.Parameters.Add(new SqlParameter("@Quantum_of_Threshold", Convert.ToInt32(txtQuantum.Text)));
              string strC = "";
              foreach (string itm in listBox1.Items)
                  strC = strC + " ," + itm;

              cmd.Parameters.Add(new SqlParameter("@Resources",strC));        
          MessageBox.Show("Insertion successfully done");


try this in the Following way

 foreach (ListItem item in ListBox1.Items)
               strc += item + ",";

//You are taking string for ListBox items instead of list Item
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shivani 2013 12-May-11 3:02am    
what is listitem here
shivani 2013 12-May-11 3:23am    
pls help
Do it like that it should work for you

listBox1.Items.Cast<object>().Aggregate((item1, item2) => item1 + "," + item2).ToString();

In your code the problem is here

foreach (string itm in listBox1.Items)
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shivani 2013 12-May-11 3:11am    
sir its desktop application .hw can i use </object>
shivani 2013 12-May-11 3:23am    
plz help
nit_singh 12-May-11 4:17am    
listBox1.Items.Cast<object>().Aggregate((item1, item2) => item1 + "," + item2).ToString();
use this. </object> is automatic generated
shivani 2013 12-May-11 4:53am    
i did
cmd.Parameters.Add(new SqlParameter("@Resources",listBox1.Items.Cast<object>().Aggregate((item1, item2) => item1 + "," + item2).ToString())); in place of
strC = strC + " ," + itm;

cmd.Parameters.Add(new SqlParameter("@Resources",strC);

insertion is successfully but in database in field resources data not fetched and written "System.Data.DataRowView,System.Data.DataRowView"
nit_singh 12-May-11 5:31am    
See the binding of the listboc. What is displayed at the run time? What is the type of ListBox?

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