ado.net查询数据库返回datatable

代码很简单，包含可以传参数

public DataTable GetDataTable(string sql, SqlParameter sqlparameter = null)
{
    using (SqlConnection conn = new SqlConnection("server=.;uid=sa;pwd=123456;database=oa"))
    {
        conn.Open();
        using (SqlCommand comm = new SqlCommand(sql, conn))
        {
            //链接式查询，断开时查询
            //com.ExecuteReader();

            //添加条件
            if (sqlparameter != null) 
            {
                comm.Parameters.Add(sqlparameter);
            }

            DataTable dataTable = new DataTable();
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(comm);
            sqlDataAdapter.Fill(dataTable);
            return dataTable;
        }
    }
}