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Class  >  dbreader  >  IsDBNull(int)
dbreader class : IsDBNull(int) method

Description

Returns a value that indicates whether the value is null.

Syntax

instance.IsDBNull(int columnIndex)

Arguments

ClassNameDescription
intcolumnIndexColumn index.

Return value

ClassDescription
boolWhether the value is null.

Sample code

1:

connection cnn = new connection("Data Source=c:\somedirectory\somedatabase.sqlite3;Version=3;");

2:

cnn.Open();

3:

command cmm = new command("select * from sometable where id < 100;", cnn);

4:

dbreader dbr = cmm.Reader(); // Command execution. Returns multi-line results.

5:

while(dbr.Read())

6:

bool isnull = dbr.IsDBNull(0);

7:

endwhile

8:

dbr.Release();

9:

cmm.Release();

10:

cnn.Close();

11:

cnn.Release();

Notes

Returns true if the specified column is null. Otherwise, returns false.

The argument should specify in a 0-based index.

If the column corresponding to the argument does not exist, an exception, UnknownException, will be thrown.

Links for reference

None.

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