Value can not be Null

[Jac]

Hey,

public class Sessie : SessieBase
{
public Contract Contract;

public Sessie()
{
Contract Contract = new Contract ();
this.Contract = Contract;
}
}

public class ContractBase
{
private string mContractNr;
public string ContractNr
{
get
{
return mContractNr;
}
set
{
mContractNr = value;
}
}

private Status mStatusCd;
public Status StatusCd
{
get
{
return mStatusCd;
}
set
{
mStatusCd = value;
}
}

public ContractBase()
{
this.StatusCd = new Status();
}
}

public class Contract: ContractBase
{
}
Somewhere in the code I want to that :

this.TxtContractnr.Text = (this.Sessie.Contract.ContractNr == null ? "" :
this.Sessie.Contract.ContractNr.ToString());

this.TxtStatus.Text = (this.Sessie.Contract.StatusCd.Desc == null ? "" :
this.Sessie.Contract.StatusCd.Desc.ToString());
I receive : A first chance exception of type 'System.ArgumentNullException'
occurred in system.windows.forms.dll

Additional information: Value cannot be null.

But that is just the test I will do.
In first case if my string is null show “�, but there is a problem with
ContractNr. How can I test such a thing?
In the second the object is created but there is no value in it. I will test
that to see which value I want to show on screen. Ok StatusCd is null, so
there is no property Desc. I understand, but the I have to test always if
StatusCd is not null and then I have to test the Desc-property.
I think it is too much, I don’t see a good and short solution for that.
Try and Catch? But then the program will be full of try and catches.

Can some one point me out.

Thanks in advance

jac

[Brad]

Change your private member to

private string mContractNr = "";

"Jac" wrote:

Hey,

public class Sessie : SessieBase
{
public Contract Contract;

public Sessie()
{
Contract Contract = new Contract ();
this.Contract = Contract;
}
}

public class ContractBase
{
private string mContractNr;
public string ContractNr
{
get
{
return mContractNr;
}
set
{
mContractNr = value;
}
}

private Status mStatusCd;
public Status StatusCd
{
get
{
return mStatusCd;
}
set
{
mStatusCd = value;
}
}

public ContractBase()
{
this.StatusCd = new Status();
}
}

public class Contract: ContractBase
{
}
Somewhere in the code I want to that :

this.TxtContractnr.Text = (this.Sessie.Contract.ContractNr == null ? "" :
this.Sessie.Contract.ContractNr.ToString());

this.TxtStatus.Text = (this.Sessie.Contract.StatusCd.Desc == null ? "" :
this.Sessie.Contract.StatusCd.Desc.ToString());
I receive : A first chance exception of type 'System.ArgumentNullException'
occurred in system.windows.forms.dll

Additional information: Value cannot be null.

But that is just the test I will do.
In first case if my string is null show “�, but there is a problem with
ContractNr. How can I test such a thing?
In the second the object is created but there is no value in it. I will test
that to see which value I want to show on screen. Ok StatusCd is null, so
there is no property Desc. I understand, but the I have to test always if
StatusCd is not null and then I have to test the Desc-property.
I think it is too much, I don’t see a good and short solution for that.
Try and Catch? But then the program will be full of try and catches.

Can some one point me out.

Thanks in advance

jac

[Christof Nordiek]

Hi Jac

you could try this
(this.Sessie.Contract.StatusCd == null || this.Sessie.Contract.StatusCd.Desc
== null)
this will yield true if StatusCd is null or StatusCd.Desc is null.

"Jac" <Ja*@discussions.microsoft.com> schrieb im Newsbeitrag
news:42**********************************@microsof t.com...

Hey,

public class Sessie : SessieBase
{
public Contract Contract;

public Sessie()
{
Contract Contract = new Contract ();
this.Contract = Contract;
}
}

public class ContractBase
{
private string mContractNr;
public string ContractNr
{
get
{
return mContractNr;
}
set
{
mContractNr = value;
}
}

private Status mStatusCd;
public Status StatusCd
{
get
{
return mStatusCd;
}
set
{
mStatusCd = value;
}
}

public ContractBase()
{
this.StatusCd = new Status();
}
}

public class Contract: ContractBase
{
}
Somewhere in the code I want to that :

this.TxtContractnr.Text = (this.Sessie.Contract.ContractNr == null ? "" :
this.Sessie.Contract.ContractNr.ToString());

this.TxtStatus.Text = (this.Sessie.Contract.StatusCd.Desc == null ? "" :
this.Sessie.Contract.StatusCd.Desc.ToString());
I receive : A first chance exception of type
'System.ArgumentNullException'
occurred in system.windows.forms.dll

Additional information: Value cannot be null.

But that is just the test I will do.
In first case if my string is null show "", but there is a problem with
ContractNr. How can I test such a thing?
In the second the object is created but there is no value in it. I will
test
that to see which value I want to show on screen. Ok StatusCd is null, so
there is no property Desc. I understand, but the I have to test always if
StatusCd is not null and then I have to test the Desc-property.
I think it is too much, I don't see a good and short solution for that.
Try and Catch? But then the program will be full of try and catches.

Can some one point me out.

Thanks in advance

jac