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Object cannot be cast from DBNull to other types.

hi all im running the following code in a web page that is calling a stored procedure to get the max value from a field

cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("@menuSubjectId",SqlDbType.Int,4).Value = Request.Form["sectionId"].ToString();
con.Open();
SqlDataReader srdr = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
//int results = 0;
while(srdr.Read())
{
results = Convert.ToInt32(srdr[0]);
}
con.Close();
}

all runs well until there is no value in the table for this particular section then i get the following error

Object cannot be cast from DBNull to other types.

if tried putting

if(srdr[0] == null) around it but its just the same

any clues

thanks

ASKER CERTIFIED SOLUTION

MogalManic

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balochdude

roughly something like that:

cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.Add("@menuSubjectId",SqlDbType.Int,4).Value = Request.Form["sectionId"].ToString();
con.Open();
SqlDataReader srdr = cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection);
//int results = 0;
while(srdr.Read())
{
results = ConvertToInt32(srdr[0]);
}
con.Close();
}

private Int32 ConvertToInt32(object value)
{
if (IsDBNull(value))
{
return 0;
}
else
{
return (Convert.ToInt32(value));
}
}

andrew67

ASKER

mega thanks