C# 已经是一个开放的数据阅读器。火星将成为现实
在ASP.NET中使用SQL时，在不同的命令和结果集之间来回切换时，我总是遇到这个问题。代码：C# 已经是一个开放的数据阅读器。火星将成为现实,c#,sql,asp.net,sql-server,C#,Sql,Asp.net,Sql Server,在ASP.NET中使用SQL时，在不同的命令和结果集之间来回切换时，我总是遇到这个问题。代码： foreach (string user in usernames) { command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 the
foreach (string user in usernames)
{
command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 then 'faculty' end as 'institution_role',batch_uid,user_id,student_id as 'passwd',firstname,middlename,lastname,email,student_id,case row_status when 0 then 'ENABLED' when 2 then 'DISABLED' end as 'row_status' from users where user_id = '" + user + "'";
SqlDataReader reader = command.ExecuteReader();
if (reader.HasRows)
{
while (reader.Read())
{
file.WriteLine(user + "|" + status);
if (overrideFramework == 0)
{
command.CommandText = "use sis_comparison_data insert into person_override values ('" + reader["system_role"].ToString() + "','" + reader["institution_role"].ToString() + "','" + reader["batch_uid"].ToString() + "','" + reader["user_id"].ToString() + "','" + reader["passwd"].ToString() + "','" + reader["firstname"].ToString() + "','" + reader["middlename"].ToString() + "','" + reader["lastname"].ToString() + "','" + reader["email"].ToString() + "','" + reader["student_id"].ToString() + "','" + overrideIndicator + "')";
command.ExecuteNonQuery();
}
validPersonCounter++;
using (StreamWriter historyFile = new StreamWriter(@"c:\bb_updates\history.txt", true))
{
historyFile.WriteLine(this.firstName + status.ToLower() + " user ID for " + user + ", SIS Integration Override: " + didOverride + ", Date: " + mn + "/" + dy + "/" + yy + " Time: " + DateTime.Now.ToString("h:mm:ss tt"));
}
}
}
else
{
invalidPersons.Add(user);
}
}
MultipleActiveResultSets=true已启用，我尝试在命令之前添加一个close.ExecuteNonQuery（）
，然后我得到了错误
读卡器关闭时读取的尝试无效
如果我将reader.Close（）
放在任何其他地方，我会得到已经打开的数据读取器错误。请告知。您不应该重复使用命令
对象。当您这样做时，您正在干扰来自ExecuteReader
调用的结果。在循环中创建一个新的SqlCommand
。您不应该重用命令
对象。当您这样做时，您正在干扰来自ExecuteReader
调用的结果。在循环中创建一个新的SqlCommand
。您不应该重用命令
对象。当您这样做时，您正在干扰来自ExecuteReader
调用的结果。在循环中创建一个新的SqlCommand
。您不应该重用命令
对象。当您这样做时，您正在干扰来自ExecuteReader
调用的结果。在循环中创建一个新的SqlCommand
。请尝试以下操作。它正确地处理读取器
，并且不重用命令
foreach (string user in usernames)
{
command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 then 'faculty' end as 'institution_role',batch_uid,user_id,student_id as 'passwd',firstname,middlename,lastname,email,student_id,case row_status when 0 then 'ENABLED' when 2 then 'DISABLED' end as 'row_status' from users where user_id = '" + user + "'";
using (var reader = command.ExecuteReader())
{
if (reader.HasRows)
{
while (reader.Read())
{
file.WriteLine(user + "|" + status);
if (overrideFramework == 0)
{
var cmd = new SqlCommand();
cmd.CommandText = "use sis_comparison_data insert into person_override values ('" + reader["system_role"].ToString() + "','" + reader["institution_role"].ToString() + "','" + reader["batch_uid"].ToString() + "','" + reader["user_id"].ToString() + "','" + reader["passwd"].ToString() + "','" + reader["firstname"].ToString() + "','" + reader["middlename"].ToString() + "','" + reader["lastname"].ToString() + "','" + reader["email"].ToString() + "','" + reader["student_id"].ToString() + "','" + overrideIndicator + "')";
cmd.ExecuteNonQuery();
}
validPersonCounter++;
using (StreamWriter historyFile = new StreamWriter(@"c:\bb_updates\history.txt", true))
{
historyFile.WriteLine(this.firstName + status.ToLower() + " user ID for " + user + ", SIS Integration Override: " + didOverride + ", Date: " + mn + "/" + dy + "/" + yy + " Time: " + DateTime.Now.ToString("h:mm:ss tt"));
}
}
}
else
{
invalidPersons.Add(user);
}
}
}
请尝试以下方法。它正确地处理读取器
，并且不重用命令
foreach (string user in usernames)
{
command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 then 'faculty' end as 'institution_role',batch_uid,user_id,student_id as 'passwd',firstname,middlename,lastname,email,student_id,case row_status when 0 then 'ENABLED' when 2 then 'DISABLED' end as 'row_status' from users where user_id = '" + user + "'";
using (var reader = command.ExecuteReader())
{
if (reader.HasRows)
{
while (reader.Read())
{
file.WriteLine(user + "|" + status);
if (overrideFramework == 0)
{
var cmd = new SqlCommand();
cmd.CommandText = "use sis_comparison_data insert into person_override values ('" + reader["system_role"].ToString() + "','" + reader["institution_role"].ToString() + "','" + reader["batch_uid"].ToString() + "','" + reader["user_id"].ToString() + "','" + reader["passwd"].ToString() + "','" + reader["firstname"].ToString() + "','" + reader["middlename"].ToString() + "','" + reader["lastname"].ToString() + "','" + reader["email"].ToString() + "','" + reader["student_id"].ToString() + "','" + overrideIndicator + "')";
cmd.ExecuteNonQuery();
}
validPersonCounter++;
using (StreamWriter historyFile = new StreamWriter(@"c:\bb_updates\history.txt", true))
{
historyFile.WriteLine(this.firstName + status.ToLower() + " user ID for " + user + ", SIS Integration Override: " + didOverride + ", Date: " + mn + "/" + dy + "/" + yy + " Time: " + DateTime.Now.ToString("h:mm:ss tt"));
}
}
}
else
{
invalidPersons.Add(user);
}
}
}
请尝试以下方法。它正确地处理读取器
，并且不重用命令
foreach (string user in usernames)
{
command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 then 'faculty' end as 'institution_role',batch_uid,user_id,student_id as 'passwd',firstname,middlename,lastname,email,student_id,case row_status when 0 then 'ENABLED' when 2 then 'DISABLED' end as 'row_status' from users where user_id = '" + user + "'";
using (var reader = command.ExecuteReader())
{
if (reader.HasRows)
{
while (reader.Read())
{
file.WriteLine(user + "|" + status);
if (overrideFramework == 0)
{
var cmd = new SqlCommand();
cmd.CommandText = "use sis_comparison_data insert into person_override values ('" + reader["system_role"].ToString() + "','" + reader["institution_role"].ToString() + "','" + reader["batch_uid"].ToString() + "','" + reader["user_id"].ToString() + "','" + reader["passwd"].ToString() + "','" + reader["firstname"].ToString() + "','" + reader["middlename"].ToString() + "','" + reader["lastname"].ToString() + "','" + reader["email"].ToString() + "','" + reader["student_id"].ToString() + "','" + overrideIndicator + "')";
cmd.ExecuteNonQuery();
}
validPersonCounter++;
using (StreamWriter historyFile = new StreamWriter(@"c:\bb_updates\history.txt", true))
{
historyFile.WriteLine(this.firstName + status.ToLower() + " user ID for " + user + ", SIS Integration Override: " + didOverride + ", Date: " + mn + "/" + dy + "/" + yy + " Time: " + DateTime.Now.ToString("h:mm:ss tt"));
}
}
}
else
{
invalidPersons.Add(user);
}
}
}
请尝试以下方法。它正确地处理读取器
，并且不重用命令
foreach (string user in usernames)
{
command.CommandText = "select case system_role when 'Z' then 'none' else 'none' end as 'system_role', case institution_roles_pk1 when 1 then 'student' when 2 then 'faculty' end as 'institution_role',batch_uid,user_id,student_id as 'passwd',firstname,middlename,lastname,email,student_id,case row_status when 0 then 'ENABLED' when 2 then 'DISABLED' end as 'row_status' from users where user_id = '" + user + "'";
using (var reader = command.ExecuteReader())
{
if (reader.HasRows)
{
while (reader.Read())
{
file.WriteLine(user + "|" + status);
if (overrideFramework == 0)
{
var cmd = new SqlCommand();
cmd.CommandText = "use sis_comparison_data insert into person_override values ('" + reader["system_role"].ToString() + "','" + reader["institution_role"].ToString() + "','" + reader["batch_uid"].ToString() + "','" + reader["user_id"].ToString() + "','" + reader["passwd"].ToString() + "','" + reader["firstname"].ToString() + "','" + reader["middlename"].ToString() + "','" + reader["lastname"].ToString() + "','" + reader["email"].ToString() + "','" + reader["student_id"].ToString() + "','" + overrideIndicator + "')";
cmd.ExecuteNonQuery();
}
validPersonCounter++;
using (StreamWriter historyFile = new StreamWriter(@"c:\bb_updates\history.txt", true))
{
historyFile.WriteLine(this.firstName + status.ToLower() + " user ID for " + user + ", SIS Integration Override: " + didOverride + ", Date: " + mn + "/" + dy + "/" + yy + " Time: " + DateTime.Now.ToString("h:mm:ss tt"));
}
}
}
else
{
invalidPersons.Add(user);
}
}
}