C#中DataTable使用

DataTable dt=new DataTable();
 
sql = "select categoryid,categoryname from categories where categorytype='5'";

cmd = new SqlCommand(sql,sqlConnDes);

SqlDataAdapter sda = new SqlDataAdapter(cmd);

sda.Fill(dt);

 for (int i = 0; i < dt.Rows.Count; i++)

{

 id = (Guid)dt.Rows[i]["categoryid"];

 categoryname = (string)dt.Rows[i]["categoryname"];

 sql = "insert into resources(id,systemid)" + "values(‘" + id + "','ead2bd60-5f79-4a6b-a97d-00455dd006bd' )";

cmd = new SqlCommand(sql,sqlConnDes);

cmd.ExecuteNonQuery();

}