Hi,
Inside my method I'm using the using-statement for data access.
Before that, I create an object of a class. This works fine.
Inside the using-statement I set properties of the class (with the data from
the database).
Getting the data works.
Setting the data doesn't work. It say's:
System.NullReferenceException: Object reference not set to an instance of an
object.
What should I do?
Thanks!
19  3927 
Arjen wrote: What should I do?
Show us the relevant code, please.
Oliver Sturm
--
omnibus ex nihilo ducendis sufficit unum
Spaces inserted to prevent google email destruction:
MSN oliver @ sturmnet.org Jabber sturm @ amessage.de
ICQ 27142619 http://www.sturmnet.org/blog
Arjen wrote: What should I do?
Show us the relevant code, please.
Oliver Sturm
--
omnibus ex nihilo ducendis sufficit unum
Spaces inserted to prevent google email destruction:
MSN oliver @ sturmnet.org Jabber sturm @ amessage.de
ICQ 27142619 http://www.sturmnet.org/blog
Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person Cache
Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person Cache
Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl... I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
I'm leaving a few lines below in sequence while cutting out others.
Arjen wrote: public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
myPerson.Id = (int)personDataReader["Id"];
So, you wonder why you get a null reference exception? You sequence of
statements in this regard says:
1. Create a Person
2. Get a person from the cache (which apparently may be null)
3. Proceed to (4) only if the person actually is null
4. Access the current person (which is null, see (3)!)
I'm not going to take wild guesses at the purpose of the whole exercise,
but I guess it's obvious that the line you have right at the start of
the method, where a new Person is created, would really belong right at
the start of the block of code where you have made sure that you haven't
found a person in the cache (after the "if (myPerson == null) {" line).
Oliver Sturm
--
omnibus ex nihilo ducendis sufficit unum
Spaces inserted to prevent google email destruction:
MSN oliver @ sturmnet.org Jabber sturm @ amessage.de
ICQ 27142619 http://www.sturmnet.org/blog
I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl... I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
I'm leaving a few lines below in sequence while cutting out others.
Arjen wrote: public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
myPerson.Id = (int)personDataReader["Id"];
So, you wonder why you get a null reference exception? You sequence of
statements in this regard says:
1. Create a Person
2. Get a person from the cache (which apparently may be null)
3. Proceed to (4) only if the person actually is null
4. Access the current person (which is null, see (3)!)
I'm not going to take wild guesses at the purpose of the whole exercise,
but I guess it's obvious that the line you have right at the start of
the method, where a new Person is created, would really belong right at
the start of the block of code where you have made sure that you haven't
found a person in the cache (after the "if (myPerson == null) {" line).
Oliver Sturm
--
omnibus ex nihilo ducendis sufficit unum
Spaces inserted to prevent google email destruction:
MSN oliver @ sturmnet.org Jabber sturm @ amessage.de
ICQ 27142619 http://www.sturmnet.org/blog
Arjen <bo*****@hotmail.com> wrote: I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
No, that's not what null means. It means you don't have a reference to
an object. Removing the using statement from the picture (because it's
irrelevant to your problem) you're doing:
if (myPerson==null)
{
myPerson.Id = (int)personDataReader["Id"];
...
}
That's trying to trying to set the property on a null reference, which
is why you're getting the exception.
--
Jon Skeet - <sk***@pobox.com> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Arjen <bo*****@hotmail.com> wrote: I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
No, that's not what null means. It means you don't have a reference to
an object. Removing the using statement from the picture (because it's
irrelevant to your problem) you're doing:
if (myPerson==null)
{
myPerson.Id = (int)personDataReader["Id"];
...
}
That's trying to trying to set the property on a null reference, which
is why you're getting the exception.
--
Jon Skeet - <sk***@pobox.com> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a glass
or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup a
coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl... I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a glass
or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup a
coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl... I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond my
understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
;-)
I see the problem (/solution) now.
Thanks!
Arjen
"Michael S" <a@b.c> schreef in bericht
news:%2****************@TK2MSFTNGP10.phx.gbl... Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a
glass or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup a
coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl...I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond
my understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl...
Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
;-)
I see the problem (/solution) now.
Thanks!
Arjen
"Michael S" <a@b.c> schreef in bericht
news:%2****************@TK2MSFTNGP10.phx.gbl... Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a
glass or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup a
coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl...I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache, if
there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...I think you missed including this line after you know myPerson is null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond
my understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl...
Here it is:
public static void LoadPersons(string name)
{
// Create person
Persons myPerson = new Person();
// Create the CacheManager object.
CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
Cache Manager");
// Check cache for requested object
myPerson = (Person)primitivesCache.GetData(name);
if (myPerson == null)
{
// Requested object is not cached; therefore, retrieve it from
// the data provider and cache it for more requests.
// Read
using (IDataReader personDataReader = Bll.PersonSelect())
{
try
{
while (personDataReader.Read())
{
// Get the values from the DataReader
myPerson.Id = (int)personDataReader["Id"];
myPerson.Name = (string)personDataReader["Name"];
myPerson.Address = (string)personDataReader["Address"];
}
}
catch (Exception ex)
{
throw (ex);
}
}
//...
}
//...
}
By this line I get the error:
myPerson.Id = (int)personDataReader["Id"];
Hope this helps!
The problem being out of cups? =)
Enough of my taunts. What you really need to do is to learn about
reference-types and value-types and how classes and structs allocates on
heap and stack. And how they don't.
Jon Skeet, who posted above, have some excellent guides on that. Better than
any book...
Happy Reading
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... ;-)
I see the problem (/solution) now.
Thanks!
Arjen
"Michael S" <a@b.c> schreef in bericht
news:%2****************@TK2MSFTNGP10.phx.gbl... Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a
glass or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup
a coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl...I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache,
if there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...
I think you missed including this line after you know myPerson is
null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond
my understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl...
> Here it is:
>
> public static void LoadPersons(string name)
> {
> // Create person
> Persons myPerson = new Person();
>
> // Create the CacheManager object.
> CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
> Cache Manager");
>
> // Check cache for requested object
> myPerson = (Person)primitivesCache.GetData(name);
>
> if (myPerson == null)
> {
> // Requested object is not cached; therefore, retrieve it from
> // the data provider and cache it for more requests.
>
> // Read
> using (IDataReader personDataReader = Bll.PersonSelect())
> {
> try
> {
> while (personDataReader.Read())
> {
> // Get the values from the DataReader
> myPerson.Id = (int)personDataReader["Id"];
> myPerson.Name = (string)personDataReader["Name"];
> myPerson.Address = (string)personDataReader["Address"];
> }
> }
> catch (Exception ex)
> {
> throw (ex);
> }
> }
> //...
> }
> //...
> }
>
>
>
> By this line I get the error:
> myPerson.Id = (int)personDataReader["Id"];
>
> Hope this helps!
>
The problem being out of cups? =)
Enough of my taunts. What you really need to do is to learn about
reference-types and value-types and how classes and structs allocates on
heap and stack. And how they don't.
Jon Skeet, who posted above, have some excellent guides on that. Better than
any book...
Happy Reading
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl... ;-)
I see the problem (/solution) now.
Thanks!
Arjen
"Michael S" <a@b.c> schreef in bericht
news:%2****************@TK2MSFTNGP10.phx.gbl... Have a look at Olivers answer.
At work I have a so called 'bug cup'. It's just a cup. Or sometimes a
glass or a mug.
But whenever I make silly mistakes, like you did; I have to give the cup
a coin.
My cup is almost always full! =)
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news6.zwoll1.ov.home.nl...I don't see what your point is.
I start with "myPerson = new Person();", try to get it from the cache,
if there is no cache then it is null.
(With null I mean that the properties like name and id are not set.)
About the while, you are correct because there is one result.
(But I use the same code where I get back multiple records)
Arjen
"Michael S" <a@b.c> schreef in bericht
news:Op**************@TK2MSFTNGP12.phx.gbl...
I think you missed including this line after you know myPerson is
null...
myPerson = new Person();
And why you try reassign this null reference in a while-loop is beyond
my understanding... =)
Happy Coding
- Michael S
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news3.zwoll1.ov.home.nl...
> Here it is:
>
> public static void LoadPersons(string name)
> {
> // Create person
> Persons myPerson = new Person();
>
> // Create the CacheManager object.
> CacheManager primitivesCache = CacheFactory.GetCacheManager("Person
> Cache Manager");
>
> // Check cache for requested object
> myPerson = (Person)primitivesCache.GetData(name);
>
> if (myPerson == null)
> {
> // Requested object is not cached; therefore, retrieve it from
> // the data provider and cache it for more requests.
>
> // Read
> using (IDataReader personDataReader = Bll.PersonSelect())
> {
> try
> {
> while (personDataReader.Read())
> {
> // Get the values from the DataReader
> myPerson.Id = (int)personDataReader["Id"];
> myPerson.Name = (string)personDataReader["Name"];
> myPerson.Address = (string)personDataReader["Address"];
> }
> }
> catch (Exception ex)
> {
> throw (ex);
> }
> }
> //...
> }
> //...
> }
>
>
>
> By this line I get the error:
> myPerson.Id = (int)personDataReader["Id"];
>
> Hope this helps!
>
"Arjen" <bo*****@hotmail.com> wrote in message
news:de**********@news1.zwoll1.ov.home.nl... Hi,
Inside my method I'm using the using-statement for data access.
Before that, I create an object of a class. This works fine.
Inside the using-statement I set properties of the class (with the data
from the database).
Getting the data works.
Setting the data doesn't work. It say's:
System.NullReferenceException: Object reference not set to an instance of
an object.
What should I do?
Provide the failing code, or better yet, a simplified example that displays
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