尝试从 Visual C# 程序更新 oracle 时出现“无效操作。连接已关闭”错误
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Getting "Invalid Operation. The Connection is closed" error while trying to update oracle from visual c# program
提问by Alex Kibler
I've got a visual c# program running, but I'm getting a connection is closed error whenever I try to update. Here's what my code looks like:
我有一个可视化 c# 程序正在运行，但是每当我尝试更新时，我都会收到连接已关闭错误。这是我的代码的样子：
private void Update()
{
try
{
String OneMachineScheduleOrder = "";
String series = "";
String oven = "";
String battery = "";
int x,y;
var sortedTextboxes = panel1.Controls
.OfType<TextBox>() // get all textboxes controls
.OrderBy(ctrl => ctrl.TabIndex); // order by TabIndex
foreach (TextBox txt in sortedTextboxes)
{
//Console.WriteLine(Convert.ToInt32(txt.TabIndex/2+1) + ": " + txt.Text);
OneMachineScheduleOrder = (txt.TabIndex / 2 + 1).ToString();
series = txt.Text.Substring(0, 1);
oven = txt.Text.Substring(1, 2);
battery = txt.Text.Substring(4).Trim();
if (Char.IsLetter(series[0]) && int.TryParse(oven, out y) && int.TryParse(battery, out x) && txt.Text[3].Equals('/'))
{
using (OracleConnection con = new OracleConnection(connectString))
{
OracleCommand cmd = connection.CreateCommand();
cmd.CommandType = CommandType.Text;
cmd.CommandText = "update Oven_Master set SERIES = '" + series + "', OVEN = '" + oven + "', BATTERY = '" + battery + "' where ONE_MACHINE_SCHEDULE_ORDER = '" + OneMachineScheduleOrder + "'";
cmd.Connection = con;
cmd.ExecuteNonQuery();
Console.WriteLine(cmd.CommandText);
con.Close();
}
}
else { MessageBox.Show("Number: " + OneMachineScheduleOrder + " Is Invalid!"); }
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
finally
{
connection.Close();
}
}
Basically, I've got a bunch of textboxes on the form that are filled in in the format A01/01. I'm sorting the textboxes into a variable, and then for each textbox, I parse out the relevent data (OneMachineScheduleOrder, series, oven, and battery). If the data is in the right format, I use an oracleConnection with a connectionstring that is global (and I checked with the debugger that it has the correct value) to create an execute and OracleCommand. Otherwise, alert the user that the data is in the wrong format.
基本上，我在表单上有一堆文本框，它们以格式A01/01. 我将文本框分类到一个变量中，然后对于每个文本框，我解析出相关数据（OneMachineScheduleOrder、系列、烤箱和电池）。如果数据格式正确，我将使用带有全局连接字符串的 oracleConnection（并使用调试器检查它是否具有正确的值）来创建执行和 OracleCommand。否则，提醒用户数据格式错误。
However, I'm getting an error that the connection is open. I tried putting a breakpoint on that line, and I'm getting that con = OracleConnection, so I can see that there isa connection. No idea where to go from here.
但是，我收到连接已打开的错误消息。我试图把在该行断点，我理解的con = OracleConnection，这样我就可以看到有是一个连接。不知道从这里去哪里。
回答by John Nicholas
try calling connection.Open before executing your command
在执行命令之前尝试调用 connection.Open
(yes, i know lol right)
（是的，我知道哈哈对）
