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Unable to cast object of type 'System.Data.DataRowView' to type 'System.IConvertible'.

I am developing a c# standalone appln ,in which depending on the combobox selecte value i have to display data in the datagrid view.
i am using mysql database
i'm getting a runtime error at
 dAdapter2.Fill(ds, "cl2");
in  private void clNamecomboBox_SelectedIndexChanged(object sender, EventArgs e)
pls help me to find a sol'n
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using MySql.Data;
using MySql.Data.MySqlClient;
 
namespace DataBinding
{
    
 
    public partial class Form1 : Form
    {
        MySqlConnection conn;
        MySqlDataAdapter dAdapter1;
        MySqlDataAdapter dAdapter2;
        DataSet ds;
        BindingSource bSource;
        public Form1()
        {
            InitializeComponent();
        }
 
        private void Form1_Load(object sender, EventArgs e)
        {
           
            string connString = @"server=localhost;database=abc;user id=root;password=kodanda;";
            string sql = @"select client_mst.client_id as id,Concat(client_no,'   ' ,client_name) as client from client_mst";
            conn = null;
 
 
            try
            {
                conn = new MySqlConnection(connString);
                conn.Open();
 
                 dAdapter1 = new MySqlDataAdapter(sql, conn);
                MySqlCommandBuilder cBuilder = new MySqlCommandBuilder(dAdapter1);
                ds = new DataSet();
                dAdapter1.Fill(ds,"Cl");
                bSource = new BindingSource();
                bSource.DataSource = ds.Tables["Cl"];
                clNamecomboBox.DataSource = bSource;
                MessageBox.Show(conn.Database);
                
                clNamecomboBox.ValueMember = "id";
                clNamecomboBox.DisplayMember = "client";
                
 
            }
            catch (Exception ex)
            {
                MessageBox.Show("Error"+ex);
            }
        }
 
        private void clNamecomboBox_SelectedIndexChanged(object sender, EventArgs e)
        {
            string sql1 = @"select notes_date,notes_message from client_notes where client_id=@cid";
            dAdapter2 = new MySqlDataAdapter(sql1, conn);
 
         
            dAdapter2.SelectCommand.Parameters.Add("@cid", MySqlDbType.Int32); 
            dAdapter2.SelectCommand.Parameters["@cid"].Value = clNamecomboBox.SelectedValue;
         
            dAdapter2.Fill(ds, "cl2");
            BindingSource bSource2 = new BindingSource();
            bSource2.DataSource = ds.Tables["cl2"];
            dataGridView1.DataSource = bSource2;
        }
        
    }
}

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0
APPIREDDY
Asked:
APPIREDDY
  • 3
1 Solution
 
tcullerCommented:
I'm guessing the error is coming from this line:
dAdapter2.SelectCommand.Parameters["@cid"].Value = clNamecomboBox.SelectedValue;

The error is telling you that the object passed to the Value property did not implement the interface System.IConvertible. In other words, it couldn't be "converted" to a satisfactory String representation. The SelectedValue property returned a DataViewRow. Maybe use clNamecomboBox.SelectedValue.Value?
0
 
APPIREDDYAuthor Commented:
if i change that line to
dAdapter2.SelectCommand.Parameters["@cid"].Value = Convert.ToInt32clNamecomboBox.SelectedValue);
i'm still getting the error.
cid  is an integer in database

0
 
APPIREDDYAuthor Commented:
clNamecomboBox.SelectedValue.Value doesn't exist
0
 
APPIREDDYAuthor Commented:
I have changed the order to
clNamecomboBox.DisplayMember = "client";
                clNamecomboBox.ValueMember = "id";
                clNamecomboBox.DataSource = bSource;
then I got it right
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