|
我正在用C#(4.0 Framework)开发CMS应用程序,它连接到远程服务器上的MySQL数据库(5.0.95)
通过MySQL Connector(6.5.4).
我在执行查询时遇到问题.
例如
我的连接字符串：
"Server=" + Options.DbServer + ";Database="+ Options.Database +";Uid=" + Options.DbUser + ";Pwd=" + Options.DbPassword + ";CharSet=utf8; Connect Timeout=30;";
我有静态类来管理数据库相关的东西,我有私人成员_connection.
private static MySqlConnection _connection;
public static MySqlConnection Connection
{
get
{
if (_connection.State != ConnectionState.Open)
_connection.Open();
return _connection;
}
set { _connection = value; }
}
这是初始化连接的方法：
public static bool Init(string cs)
{
_connection = new MySqlConnection(cs);
MySqlCommand command = new MySqlCommand("SET NAMES utf8",Connection);
command.ExecuteNonQuery();
return true;
}
这是我得到异常的方法：
public static bool InsertRecord(MySqlCommand command)
{
command.Connection = Connection;
if(command.ExecuteNonQuery() > 0)
return true;
return false;
}
command.ExecuteNonQuery()抛出异常：在命令执行期间遇到致命错误.
这是堆栈跟踪……
MySql.Data.MySqlClient.MySqlException was unhandled
Message=Fatal error encountered during command execution.
Source=MySql.Data
ErrorCode=-2147467259
Number=0
StackTrace:
at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
at MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery()
at CMS.Database.InsertRecord(MySqlCommand command) in C:_myStuffVS2010CMSCMSDatabase.cs:line 95
at CMS.frmAddItem.btnDo_Click(Object sender,EventArgs e) in C:_myStuffVS2010CMSCMSfrmAddItem.cs:line 138
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m,MouseButtons button,Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd,Int32 msg,IntPtr wparam,IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID,Int32 reason,Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason,ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason,ApplicationContext context)
at System.Windows.Forms.Application.RunDialog(Form form)
at System.Windows.Forms.Form.ShowDialog(IWin32Window owner)
at System.Windows.Forms.Form.ShowDialog()
at CMS.frmMain.btnNovi_Click(Object sender,EventArgs e) in C:_myStuffVS2010CMSCMSfrmMain.cs:line 381
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m,ApplicationContext context)
at System.Windows.Forms.Application.RunDialog(Form form)
at System.Windows.Forms.Form.ShowDialog(IWin32Window owner)
at System.Windows.Forms.Form.ShowDialog()
at CMS.frmLogin.DoLogin() in C:_myStuffVS2010CMSCMSfrmLogin.cs:line 55
at CMS.frmLogin.button2_Click(Object sender,EventArgs e) in C:_myStuffVS2010CMSCMSfrmLogin.cs:line 31
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m,ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at CMS.Program.Main() in C:_myStuffVS2010CMSCMSProgram.cs:line 18
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly,String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile,Evidence assemblySecurity,String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext,ContextCallback callback,Object state,Boolean ignoreSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext,Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException: MySql.Data.MySqlClient.MySqlException
Message=Fatal error encountered attempting to read the resultset.
Source=MySql.Data
ErrorCode=-2147467259
Number=0
StackTrace:
at MySql.Data.MySqlClient.MySqlDataReader.NextResult()
at MySql.Data.MySqlClient.MySqlCommand.ExecuteReader(CommandBehavior behavior)
InnerException: MySql.Data.MySqlClient.MySqlException
Message=Reading from the stream has failed.
Source=MySql.Data
ErrorCode=-2147467259
Number=0
StackTrace:
at MySql.Data.MySqlClient.MySqlStream.LoadPacket()
at MySql.Data.MySqlClient.MySqlStream.ReadPacket()
at MySql.Data.MySqlClient.NativeDriver.GetResult(Int32& affectedRow,Int32& insertedId)
at MySql.Data.MySqlClient.Driver.GetResult(Int32 statementId,Int32& affectedRows,Int32& insertedId)
at MySql.Data.MySqlClient.Driver.NextResult(Int32 statementId,Boolean force)
at MySql.Data.MySqlClient.MySqlDataReader.NextResult()
InnerException: System.IO.EndOfStreamException
Message=Attempted to read past the end of the stream.
Source=MySql.Data
StackTrace:
at MySql.Data.MySqlClient.MySqlStream.ReadFully(Stream stream,Byte[] buffer,Int32 offset,Int32 count)
at MySql.Data.MySqlClient.MySqlStream.LoadPacket()
InnerException:
有什么建议？
最佳答案
我注意到你打开了连接,但是当你完成它们时你不会关闭它们.我更喜欢在需要时打开连接的方法,而不是在它们尚未打开时打开连接.它们可能是陈旧的.
缓存连接字符串但不缓存连接本身.
public static string ConnectionString {get;set;}
public static bool InsertRecord(sql)
{
bool success = false;
using (var con = new Connection(ConnectionString)){
var command = new SqlCommand(sql,con);
success = (command.ExecuteNonQuery() > 0);
}
return success;
}
当不再需要资源时,应释放资源.
（编辑：李大同）
【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!
|
