关lDbConnection 与SqlConnection的疑惑
lDbConnection con = new SqlConnection("server=.;database=MyQQ;uid=sa;pwd=sa");IDbCommand cmd = new SqlCommand("select top 3 * from Users", con); //为什么为里说lDbConnection 不能转换为SqlConnection类型
//SqlConnection已经实现lDbConnection 接口,为什么这里用con出错。有些不清楚,大家帮忙看下 --------------------编程问答-------------------- 虽然SqlConnection已经实现IDbConnection接口,但IDbConnection并不是SqlCommand方法可接收的参数,你需要强制转换一下:
IDbConnection con = new SqlConnection("server=.;database=MyQQ;uid=sa;pwd=sa");
IDbCommand cmd = new SqlCommand("select top 3 * from Users", (IDbConnection)con);
补充:.NET技术 , C#