sql data type bit

I have sql data type bit and i want to ask

if(dr[2] != null开发者_StackOverflow中文版)

What changes should make it? Sorry for the mistakes I'm not local.

To check if the column value is NULL, use DBNull.Value:

if (dr[2] != DBNull.Value)

Assuming dr is a DataReader, calling dr.IsDBNull(2) will tell you whether it's null.

I wrote like this and the value is NULL dr[2] != System.DBNull.Value and this answer Object cannot be cast from DBNull to other types.