object error

Maneesh A N

public ClsConnect()
{
strConnect = ConfigurationManager.ConnectionStrings["sqlConnection"].ConnectionString;
conSql = new SqlConnection(strConnect);
}

here i got error ....Object reference not set to an instance of an object.

8 Replies

Know the answer? Post it — somebody with the same question will find it here.

Suthish Nair12y ago
Hi Maneesh,

If you want to learn, avoid spoon feeding. Why don't just dive into the code, debug each line of code and check why the code is failing.

How to: Generate or find Connection String from Visual Studio

error-object-reference-not-set-to-an-instance-of-an-object
Prasenjit Dey12y ago

have you give a proper server name there means in ConnectionString in web.config. You have given that "server =.". Is it right? At least write there "server = localhost" if you are using local database or give the database IP address
(like server = " 192.168.1.563 ") if you are using a remote database server.
Maneesh A N12y ago
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;

namespace EXAMPLE1
{
class ClsConnect
{
public static SqlConnection conSql;
//public string strConnect;
//public ClsConnect()
//{
// SqlConnection con = new SqlConnection();
// strConnect =ConfigurationManager.ConnectionStrings["sqlConnection"].ConnectionString;
// conSql = new SqlConnection(strConnect);

//}

public ClsConnect()
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["sqlConnection"].ToString());

}
}
Maneesh A N12y ago
i can not find ...please help mee
Maneesh A N12y ago
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 System.Data.SqlClient;

namespace EXAMPLE1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
ClsConnect consql = new ClsConnect();
int block = 0;
int G_iItemID = 0;

private void Form1_Load(object sender, EventArgs e)
{
groupBox1.Enabled = false;
}

private void General_keydown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
if (this.GetNextControl(ActiveControl, true) != null)
{
e.Handled = true;
{
this.GetNextControl(ActiveControl, true).Focus();
}
}

}
}

private void BtnAdd_Click(object sender, EventArgs e)
{
groupBox1.Enabled = true;
txtItemName.Focus();
}

private void BtnExit_Click(object sender, EventArgs e)
{
this.Close();
}

private void BtnSave_Click(object sender, EventArgs e)

{
if (G_iItemID == 0)
{
block = 0;
}
else
{
block = 1;
}
fnItemSaveUpdate(0);

}
private void fnItemSaveUpdate(int block)
{
string Returnvalue = "";
{
try
{
string ItemName = txtItemName.Text;
string Unit = txtUnit.Text;
string Amount = txtAmount.Text;

SqlDataAdapter sda = new SqlDataAdapter();
sda.SelectCommand = new SqlCommand("PrcItemSaveUpdate", ClsConnect.conSql);
sda.SelectCommand.CommandType = CommandType.StoredProcedure;
sda.SelectCommand.Parameters.AddWithValue("@iItemID", G_iItemID);
sda.SelectCommand.Parameters.AddWithValue("@vItemName", ItemName);
sda.SelectCommand.Parameters.AddWithValue("@vUnit", Unit);
sda.SelectCommand.Parameters.AddWithValue("@iAmount", Amount);
sda.SelectCommand.Parameters.AddWithValue("@block", block);

string s = ClsConnect.conSql.State.ToString();
if (s == "open")
{
ClsConnect.conSql.Close();
}
ClsConnect.conSql.Open();
G_iItemID = Convert.ToInt32(sda.SelectCommand.ExecuteScalar());
ClsConnect.conSql.Close();

if (block == 0)
{
MessageBox.Show("ITEM SAVED");
}

else
{
MessageBox.Show("ITEM UPDATED");
}

}

catch (Exception ex)
{
Returnvalue=ex.Message;
}
}

}




}

}
config file
Prasenjit Dey12y ago
public ClsConnect()
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["sqlConnection"].ToString());

}

use that code. And must be check that "sqlConnection" is declare perfectly in ConnectionString in your web.config file
12y ago
Hi Maneesh,
make sure the connection name 'sqlconnection' is available in your .config file.
Suthish Nair12y ago
Because, the connection with database is not establishing here.. Check your connection string..

http://stopdebugging.wordpress.com/2013/11/06/error-object-reference-not-set-to-an-instance-of-an-object/