deb081900 0 Newbie Poster

Hi All

I got lots of help from this site

Here I am facing 1 simple problem but can't point it out, So I need urgent help from you all. I am using Windows 7, VS C# 2008, Access 2007
My Access database have 1 photo column of OLE Object.
Here is the code of C# which is working fine if it work without photo part - After the code Exception which is thrown is mention pls see it All the important section are highlighted

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.OleDb;
using System.Data.Sql;
using System.Globalization;
using System.IO;
using Microsoft.VisualBasic;
namespace StudentInformation
{    
public partial class Form4 : Form    
{        
OleDbCommand aCommand;        
OleDbConnection aConnection;        
MemoryStream ms;        
//byte[] photo_aray;        
String queryStr;        
//All Variables are decleared here        
//photo                        
public Form4()        
{            
InitializeComponent();            
aConnection = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=D:\\KVSoftware\\KVStudent\\KV1StudentInformation.mdb");            Console.WriteLine("Form4 started");        
}        
private void button2_Click(object sender, EventArgs e)        
{            
try
            
{                 
*/entered values are stored in local variables for eg.                 v_admission_no=textBox3.Text; v_student_name=textBox6.Text;                v_admitted_class=textBox11.Text;  v_admission_date = dateTimePicker1.Value.ToString(); */

queryStr="INSERT INTO PersonalDetail(admission_no,student_name,admitted_class,admission_date,present_class,present_section,roll_no,dob,gender,caste,minority_status,house,cbse_xth_roll,previous_school,conveyance_mode,remark,photo) VALUES('" + v_admission_no + "','" + v_student_name + "','" + v_admitted_class + "','" + v_admission_date + "','" + v_present_class + "','" + v_present_section + "','" + v_roll_no + "','" + v_dob + "','" + v_gender + "','" + v_caste + "','" +  v_minority_status + "','" + v_house + "','" + v_cbse_xth_roll + "','" + v_previous_school + "','" + v_conveyance_mode + "','" + v_remark + "',@photo)";     
               
Console.WriteLine("query Build");                
conv_photo();          
aConnection.Open();                
aCommand = new OleDbCommand(queryStr, aConnection);                
Console.WriteLine("query Executed on Connection");                
int check=aCommand.ExecuteNonQuery();                
Console.WriteLine("query Executed");                
if (check == 1)                
{                                      
label1.Visible = true;                
}            
}            
catch (Exception ex)            
{                
Console.WriteLine("Error: {0}", ex.Message);            
}            
finally           
{                
MessageBox.Show("Finally of Personal");                
aConnection.Close();            
}         
}        
void conv_photo()        
{            
try          
{                
//converting photo to binary data                if (pictureBox1.Image != null)                
{                    
//using FileStream:(will not work while updating, if image is not changed)                    
//FileStream fs = new FileStream(openFileDialog1.FileName, FileMode.Open, FileAccess.Read);                    //byte[] photo_aray = new byte[fs.Length];                    
//fs.Read(photo_aray, 0, photo_aray.Length);                      
//using MemoryStream:                    Console.WriteLine("Cov1");                    
ms = new MemoryStream();                    
Console.WriteLine("Cov2");                    
pictureBox1.Image.Save(ms, ImageFormat.Jpeg);                    
Console.WriteLine("Cov3");                    
Console.WriteLine(ms.Length);                    
byte[] photo_aray = new byte[ms.Length];                    
Console.WriteLine("Cov4");                    
ms.Position = 0;                    
Console.WriteLine("Cov5");                    
ms.Read(photo_aray, 0, photo_aray.Length);                    
Console.WriteLine("Cov6");                    
aCommand.Parameters.AddWithValue("@photo", photo_aray);                    
Console.WriteLine("Cov7");                
}            
}            
catch (Exception ne)            
{                
Console.WriteLine("Error: {0}", ne.Message);            
}        
}             
private void tabPage2_Enter(object sender, EventArgs e)        
{            
label52.Text = v_admission_no; label53.Text = v_student_name;        
}        
private void button1_Click(object sender, EventArgs e)        
{            
openFileDialog1.Filter = "jpeg|*.jpg|bmp|*.bmp|all files|*.*";            
DialogResult res = openFileDialog1.ShowDialog();            
if (res == DialogResult.OK)            
{                
pictureBox1.Image = Image.FromFile(openFileDialog1.FileName);        
}         
}   
}
}

Exception Part This is the

returned data from Login table
Form4 started
query Build
Cov1
Cov2
A first chance exception of type 'System.NullReferenceException' occurred in StudentInformation.exeA first chance exception of type 'System.Data.OleDb.OleDbException' occurred in System.Data.dll
Cov3
128755
Cov4
Cov5
Cov6
Error: Object reference not set to an instance of an object.query Executed on Connection
Error: No value given for one or more required parameters.The thread 0x250 has exited with code 0 (0x0).
The thread 0x1598 has exited with code 0 (0x0).
The program '[1480] StudentInformation.vshost.exe: Managed' has exited with code 0 (0x0).

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