Getting object reference not set to an instance of object for Business layer code attached

Question

I have this Business Layer/ Contactentry.ascx page which calls a stored prcoedure to insert data into sql database and then the page below calls this business layer method. the issue is this method

aspdotnet.BusinessLogicLayer.ContactEntry  AddEntry = 
    new ContactEntry(Convert.ToInt32(Session["ContactID"].ToString())
    ,Title,FirstName,MiddleName,LastName,JobTitle,Company,Website,OfficePhone
    ,HomePhone,Mobile,Fax,OEmail,PEmail,OAStreet,OACity,OAState,OACountry
    ,OAZipCode,PAStreet,PACity,PAState,PACountry,PAZipCode);

throws an error saying object refernece not set to an instance of an object although I have entered all values for the text fields.

using System;
using System.Data;
using System.Configuration;
using aspdotnet.DataAccessLayer;

namespace  aspdotnet.BusinessLogicLayer
{
    public class ContactEntry
    {
        private int _ContactID;
        private string _Title;
        private string _FirstName;
        private string _MiddleName;
        private string _LastName;
        private string _JobTitle;
        private string _Company;
        private string _Website; 
        private string _OfficePhone; 
        private string _HomePhone; 
        private string _Mobile; 
        private string _Fax; 
        private string _OEmail;
        private string _PEmail;
        private string _OAStreet;
        private string _OACity; 
        private string _OAState; 
        private string _OACountry;
        private string _OAZipCode;
        private string _PAStreet; 
        private string _PACity; 
        private string _PAState; 
        private string _PACountry;
        private string _PAZipCode;

        public int ContactID
        {
            get { return _ContactID; }
            set { _ContactID = value; }
        }
        public string Title
        {
            get { return _Title; }
            set { _Title = value; }
        }
        public string FirstName
        {
            get { return _FirstName; }
            set { _FirstName = value; }
        }
        public string MiddleName
        {
            get { return _MiddleName; }
            set { _MiddleName = value; }
        }
        public string LastName
        {
            get { return _LastName; }
            set { _LastName = value; }
        }

        public string JobTitle
        {
            get { return _JobTitle; }
            set { _JobTitle = value; }
        }

        public string Company
        {
            get { return _Company; }
            set { _Company = value; }
        }

        public string Website
        {
            get { return _Website; }
            set { _Website = value; }
        }

        public string OfficePhone
        {
            get { return _OfficePhone; }
            set { _OfficePhone = value; }
        }
        public string HomePhone
        {
            get { return _HomePhone; }
            set { _HomePhone = value; }
        }
        public string Mobile
        {
            get { return _Mobile; }
            set { _Mobile = value; }
        }
        public string Fax
        {
            get { return _Fax; }
            set { _Fax = value; }
        }
        public string OEmail
        {
            get { return _OEmail; }
            set { _OEmail = value; }
        }
        public string PEmail
        {
            get { return _PEmail; }
            set { _PEmail = value; }
        }

        public string OAStreet
        {
            get { return _OAStreet; }
            set { _OAStreet = value; }
        }

        public string OACity
        {
            get { return _OACity; }
            set { _OACity = value; }
        }
        public string OAState
        {
            get { return _OAState; }
            set { _OAState = value; }
        }
        public string OACountry
        {
            get { return _OACountry; }
            set { _OACountry = value; }
        }
        public string OAZipCode
        {
            get { return _OAZipCode; }
            set { _OAZipCode = value; }
        }
        public string PAStreet
        {
            get { return _PAStreet; }
            set { _PAStreet = value; }
        }
        public string PACity
        {
            get { return _PACity; }
            set { _PACity = value; }
        }
        public string PAState
        {
            get { return _PAState; }
            set { _PAState = value; }
        }

        public string PACountry
        {
            get { return _PACountry; }
            set { _PACountry = value; }
        }

        public string PAZipCode
        {
            get { return _PAZipCode; }
            set { _PAZipCode = value; }
        }
        public ContactEntry()
        {
        }
        public ContactEntry(int ContactID, string Title, string FirstName, string MiddleName, string LastName, string JobTitle, string Company, string Website, string OfficePhone, string HomePhone, string Mobile, string Fax, string OEmail, string PEmail, string OAStreet, string OACity, string OAState, string OACountry, string OAZipCode, string PAStreet, string PACity, string PAState, string PACountry, string PAZipCode)
        {

             _ContactID=ContactID; 
             _Title=Title;
             _FirstName = FirstName;
             _MiddleName = MiddleName;
             _LastName = LastName;
             _JobTitle = JobTitle;
             _Company = Company;
             _Website = Website;
             _OfficePhone = OfficePhone;
             _HomePhone = HomePhone;
             _Mobile = Mobile;
             _Fax = Fax;
             _OEmail=OEmail;
             _PEmail=PEmail;
             _OAStreet = OAStreet;
             _OACity = OACity;
             _OAState = OAState;
             _OACountry =OACountry;
             _OAZipCode = OAZipCode;
             _PAStreet = PAStreet;
             _PACity = PACity;
             _PAState = PAState;
             _PACountry = PACountry;
             _PAZipCode = PAZipCode;
        }

        public bool Save()
        {   
            if (_ContactID == 0)
                return Insert();
           else
              return  Update();
        }

        private bool Insert()
        {
            _ContactID = Convert.ToInt32(DBTask.ExecuteScalar(System.Configuration.ConfigurationManager.AppSettings[Web.Global.CfgKeyConnString], "ContactInfo_Insert", _Title, _FirstName, _MiddleName, _LastName, _JobTitle, _Company, _Website, _OfficePhone, _HomePhone, _Mobile, _Fax, _OEmail, _PEmail, _OAStreet, _OACity, _OAState, _OACountry, _OAZipCode, _PAStreet, _PACity, _PAState, _PACountry, _PAZipCode));
        return (0 < _ContactID);
        }
        public static void Remove(int ContactID)
        {           
        DBTask.ExecuteNonQuery(System.Configuration.ConfigurationManager.AppSettings[Web.Global.CfgKeyConnString], "ContactInfo_Delete", ContactID);
        }
        private bool Update()
        {
            try
            {
                DBTask.ExecuteNonQuery(System.Configuration.ConfigurationManager.AppSettings[Web.Global.CfgKeyConnString], "ContactInfo_Update", _ContactID, _Title, _FirstName, _MiddleName, _LastName, _JobTitle, _Company, _Website, _OfficePhone, _HomePhone, _Mobile, _Fax, _OEmail, _PEmail, _OAStreet, _OACity, _OAState, _OACountry, _OAZipCode, _PAStreet, _PACity, _PAState, _PACountry, _PAZipCode);             
                return true;
            }
            catch 
            {
                return false;
            }
        }
        public void  LoadContact(int ContactID)
        {
            DataSet ds = DBTask.ExecuteDataset(System.Configuration.ConfigurationManager.AppSettings[Web.Global.CfgKeyConnString], "ContactInfo_GetContact", ContactID);
            DataRow row = ds.Tables[0].Rows[0];         
            _ContactID=Convert.ToInt32(row["ContactID"].ToString()); 
            _Title=row["Title"].ToString();  
            _FirstName = row["FirstName"].ToString();  
            _MiddleName = row["MiddleName"].ToString();  
            _LastName = row["LastName"].ToString();  
            _JobTitle = row["JobTitle"].ToString();  
            _Company = row["Company"].ToString();
            _Website = row["Website"].ToString();
            _OfficePhone = row["OfficePhone"].ToString();
            _HomePhone =  row["HomePhone"].ToString();
            _Mobile =  row["Mobile"].ToString();
            _Fax = row["Fax"].ToString();
            _OEmail=row["OfficialEmail"].ToString();
            _PEmail=row["PersonalEmail"].ToString();
            _OAStreet = row["OAStreet"].ToString();
            _OACity = row["OACity"].ToString();
            _OAState = row["OAState"].ToString();
            _OACountry =row["OACountry"].ToString();
            _OAZipCode = row["OAZip"].ToString();
            _PAStreet = row["PAStreet"].ToString();
            _PACity = row["PACity"].ToString();
            _PAState = row["PAState"].ToString();
            _PACountry = row["PACountry"].ToString();
            _PAZipCode = row["PAZip"].ToString();           

        }

    }
}



Insert form calling above function from Business Layer:

private void btnSave_Click(object sender, System.EventArgs e)
        {
            string Title =  drplstTitle.SelectedItem.Text;    
            string FirstName = txtFirstName.Text;
            string MiddleName = txtMiddleName.Text;
            string LastName = txtLastName.Text;
            string JobTitle = this.txtJobTitle.Text;
            string Company = this.txtCompany.Text;
            string Website = this.txtWebSite.Text;
            string OfficePhone = this.txtOfficePhone.Text;
            string HomePhone = this.txtHomePhone.Text;
            string Mobile = this.txtMobile.Text;
            string Fax = this.txtFax.Text;
            string OEmail = this.txtOfficialEmail.Text;
            string PEmail = this.txtPersonalEmail.Text;
            string OAStreet = this.txtOAStreet.Text;
            string OACity = this.txtOACity.Text ;
            string OAState = this.txtOAState.Text;
            string OACountry = this.txtOACountry.Text;
            string OAZipCode = this.txtOAZipCode.Text;
            string PAStreet = this.txtPAStreet.Text;
            string PACity = this.txtPACity.Text;
            string PAState = this.txtPAState.Text;
            string PACountry = this.txtPACountry.Text;
            string PAZipCode = this.txtPAZipCode.Text;
            aspdotnet.BusinessLogicLayer.ContactEntry  AddEntry = 
new ContactEntry(Convert.ToInt32(Session["ContactID"].ToString()),Title,FirstName,MiddleName,LastName,JobTitle,Company,Website,OfficePhone,HomePhone,Mobile,Fax,OEmail,PEmail,OAStreet,OACity,OAState,OACountry,OAZipCode,PAStreet,PACity,PAState,PACountry,PAZipCode);
            //AddEntry.Save();


        }

I get object reference not set to an insance of object right after above method aspdotnet.BusinessLogicLayer.ContactEntry above. I see all values are being passed when I am debugging. I entered all values when entering values above but it still errors out. Not sure what I am missing. Please help , appreciate your time.

Answer 1

Check your Session["ContactID"].

Consider changing your code to something like this...

//...
string PAState = this.txtPAState.Text; 
string PACountry = this.txtPACountry.Text; 
string PAZipCode = this.txtPAZipCode.Text;
string contactIDstr = Session["ContactID"] as string;
int contactID = 0;

if(!String.IsNullOrEmpty(conactIDStr))
    Int32.TryParse(contactIDStr, out contactID);

aspdotnet.BusinessLogicLayer.ContactEntry AddEntry = new ContactEntry(
    contentID,
    Title,
    FirstName,MiddleName,LastName,JobTitle,Company,
    Website,OfficePhone,HomePhone,Mobile,Fax,OEmail,PEmail,
    OAStreet,OACity,OAState,OACountry,OAZipCode,PAStreet,PACity,PAState,PACountry,PAZipCode
); 

Answer 2

This line is suspicious:

Convert.ToInt32(Session["ContactID"].ToString())

Session["ContactID"] may return null and calling ToString() on null blows up. Convert.ToInt32(null) wouldn't throw an error - it would return 0, not NULL.

Answer 3

You to handle Session["ContactID"] for nulls and Empty before Converting it to Int32

Example :

ContactEntry cEntry = null;
    if(Session["ContactID"] != null)
    {
        if(!String.IsNullOrEmpty(Session["ContactID"]))
        {
        cEntry = new ContactEntry(Convert.ToInt32(Session["ContactID"].ToString());
        }
    }