asked on

Check value of a bit field in a dataset

Greetings

I am trying to check the value of a bit field and based on that, to update a label. I am getting an erro:
Error      1      Operator '==' cannot be applied to operands of type 'object' and 'bool'      D:\MyStuff - Allan\Training\School_Keeper_ASP\Pages_Admin\Lookup_Religion.aspx.cs      74      13      D:\...\School_Keeper_ASP\

My code:
if (dsReligions.Tables["Religions_List"].Rows[lbxReligions.SelectedIndex]["RL_System"] == true)
Label4.Text = "System";
else
Label4.Text = "NON System";

My sql, that ceated the table:
CREATE TABLE [dbo].[Religions_List](
RL_No                  smallint IDENTITY(1,1) not null,
RL_Name            varchar(50) not null,
RL_System            bit not null default(0),
CONSTRAINT [PK_Religions_List] PRIMARY KEY.......

ASKER CERTIFIED SOLUTION

Elvio Lujan

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SOLUTION

nisarkhan

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nisarkhan

1 means true
0 means false

allanmark

ASKER

int xyz = (int)dsReligions.Tables["Religions_List"].Rows[lbxReligions.SelectedIndex]["RL_System"];
if ((int)dsReligions.Tables["Religions_List"].Rows[lbxReligions.SelectedIndex]["RL_System"] == 1)
Label4.Text = "System";
else
Label4.Text = "NON System";

ERROR: Specified cast is not valid.

SOLUTION

Elvio Lujan

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allanmark

ASKER

Got it!!

Did as you suggested - the break point thingy ... value was TRUE. SO I played around and:

if ((BOOL)dsReligions.Tables["Religions_List"].Rows[lbxReligions.SelectedIndex]["RL_System"] == true)
Label4.Text = "System";
else
Label4.Text = "NON System";

THANK YOU!!!

AGBrown

As a follow up note:

SQL Server data types do correspond to CLR data types:
bigint -> long
int -> int
smallint -> short
tinyint -> byte
bit -> bool

Be careful to always explicitly cast the result of a function (such as the column indexer of a datatable row, or the GetValue method of a data reader) to the CLR type you want before comparing to other values or assigning to variables.
e.g.

bool blnSystem = (bool)dsReligions.Tables["Religions_List"].Rows[lbxReligions.SelectedIndex]["RL_System"];

short shNo = (short)myReader.GetValue(0); // same as myReader.GetInt16(0)

All you have to be careful of are null database values - if you could have a NULL in a column, you can use a nullabe data type:

short? shNo = (short)myReader.GetValue(0); // same as myReader.GetInt16(0)

Andy