I need some help with checking for null string value in VB.Net. Since I

can not use VBScript IsNull function anymore, I would like to know which

function I can use to check for nulls.

thanks

How about this from the BOL



IsDbNull Function

See Also

Example

IsArray Function | IsDate Function | IsNumeric Function | TypeName

Function | Object Data Type

[This topic is part of a beta release and is subject to change in future

releases. Blank topics are included as placeholders.]

Returns a Boolean value that indicates whether an expression contains no

valid data (Null).

IsDbNull(expression)

The required expression argument is an Object containing a numeric

expression or string expression.

Remarks

IsDbNull returns True if expression is DbNull; otherwise, IsDbNull

returns False. If expression consists of more than one variable, DbNull

in any constituent variable causes True to be returned for the entire

expression.

The DbNull value indicates that the Object contains no valid data.

DbNull is not the same as Nothing, which indicates that a variable has

not yet been initialized. It is also not the same as a zero-length

string (""), which is sometimes referred to as a null string.

Important   Use the IsDbNull function to determine whether an expression

contains a DbNull value. Expressions that you might expect to evaluate

to True under some circumstances, such as If Var =3D DbNull and If Var 

<>

DbNull, are always False. This is because any expression containing a

DbNull is itself DbNull and, therefore, False.





-----Original Message-----

From: Tom Brzeski [mailto:tom.brzeski@o...]

Sent: Wednesday, January 17, 2001 9:22 AM

To: ASP+

Subject: [aspx] IsNull function, please help!!



I need some help with checking for null string value in VB.Net. Since I

can not use VBScript IsNull function anymore, I would like to know which

function I can use to check for nulls.

thanks

Yeah you are right that IsNull function is no more....and also NULL is also

no more....so there is no question of checking NULLS....now if you want to

check nulity in a object variable than.....you have to use IsDBNull

function......



Krishna Kant Baderia 

Sr. Developer 

Solutions Infosystems Pvt. Ltd. 

www.Solutionsny.com 



Phone : (O) +xx-xx-xxxxxxx 

           (R) +xx-xx-xxxxxxx / xxxxxxx 





-----Original Message-----

From: Tom Brzeski [mailto:tom.brzeski@o...]

Sent: Wednesday, January 17, 2001 10:52 PM

To: ASP+

Subject: [aspx] IsNull function, please help!!





I need some help with checking for null string value in VB.Net. Since I

can not use VBScript IsNull function anymore, I would like to know which

function I can use to check for nulls.

thanks

You can use:



Convert.IsDBNull(value)

where value is the item you are checking for null



or



if you are using a DataRow, SQLDataReader, or ADODataReader object, you can

use:

obj.IsNull(ord)

where ord is the column ordinal



Also note that in VB, null is referenced by the keyword Nothing





----jonathan goodyear, mcsd, mcp, cls

president@a...





----- Original Message -----

From: "Krishnakant Baderia" <krishnabaderia@s...>

To: "ASP+" <aspx@p...>

Sent: Friday, January 19, 2001 1:12 AM

Subject: [aspx] RE: IsNull function, please help!!





> Yeah you are right that IsNull function is no more....and also NULL is

also

> no more....so there is no question of checking NULLS....now if you want to

> check nulity in a object variable than.....you have to use IsDBNull

> function......

>

> Krishna Kant Baderia

> Sr. Developer

> Solutions Infosystems Pvt. Ltd.

> www.Solutionsny.com

>

> Phone : (O) +xx-xx-xxxxxxx

>            (R) +xx-xx-xxxxxxx / xxxxxxx

>

>

> -----Original Message-----

> From: Tom Brzeski [mailto:tom.brzeski@o...]

> Sent: Wednesday, January 17, 2001 10:52 PM

> To: ASP+

> Subject: [aspx] IsNull function, please help!!

>

>

> I need some help with checking for null string value in VB.Net. Since I

> can not use VBScript IsNull function anymore, I would like to know which

> function I can use to check for nulls.

> thanks

>

>