我有问题，只读第一条记录并且必须是来自数据库的 5 条记录。帮我解决这个问题。我在 1 个命令中有 3 个请求，我认为它对我来说不正常。
DB中记录截图
结果
var model = new List<WorkPeriod1>();
MySqlCommand cmd2 = new MySqlCommand("SELECT DISTINCT target_date FROM work_period w, aspnetusers u WHERE u.Id=w.id_manager AND u.UserType=0 AND u.Id_num<>0 AND u.IsActive = TRUE AND w.target_date >= DATE_SUB('2018-04-21',INTERVAL 7 DAY);" +
"SELECT w.start ,w.finish, WEEKDAY(w.target_date) dayssa FROM aspnetusers u , work_period w WHERE u.Id=w.id_manager AND u.UserType=0 AND u.Id_num<>0 AND u.IsActive = TRUE AND target_date >= DATE_SUB('2018-04-21',INTERVAL 7 DAY);" +
"SELECT DISTINCT u.ContactName ,w.description FROM aspnetusers u , work_period w WHERE u.Id=w.id_manager AND u.UserType=0 AND u.Id_num<>0 AND u.IsActive = TRUE AND w.target_date >= DATE_SUB('2018-04-21',INTERVAL 7 DAY);", conn);
conn.Open();
using (conn)
{
MySqlDataReader reader = cmd2.ExecuteReader();
while (reader.HasRows)
//for (int i = 0; i < reader.FieldCount; i++)
{
var workperiod = new WorkPeriod1();
if (reader.Read())
{
workperiod.Rtarget_date = reader.GetDateTime(0);
}
reader.NextResult();
if (reader.Read())
{
workperiod.RStart = Convert.ToDateTime(reader.GetString(0));
workperiod.RFinish = Convert.ToDateTime(reader.GetString(1));
workperiod.DWA = Convert.ToInt32(reader.GetInt32(2));
}
reader.NextResult();
if (reader.Read())
{
workperiod.RDescr = reader.GetString(1);
workperiod.RContactName = reader.GetString(0);
}
reader.NextResult();
model.Add(workperiod);
}
reader.Close();
最佳答案
使用 while 而不是 if:
if (reader.HasRows)
{
while (reader.Read())
{
.........
关于c# - 如何通过MySqlReader C#读取多个请求，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/50059048/