.net-4.0

问题 I have an user form in application. Some fields are validated. If field has wrong value red border is drawn for this control. It is made by handling Paint event for this control. I extended TextField and DateTimePicker to get Paint event from those classes objects. I have problem with NumericUpDown class. It does fire Paint event properly but invoking ControlPaint.DrawBorder(e.Graphics, eClipRectangle, Color.Red, ButtonBorderStyle.Solid); does completely nothing. Any ideas or suggestions? If

问题 This question already has answers here : Closed 10 years ago . Possible Duplicate: byte[] array pattern search Hello, Whats the best way to search if a byte[] is in another byte[]. For example byte[] first = new byte[] { 0x01, 0x02, 0x03, 0x04, 0x05 }; byte[] second = new byte[] { 0x01, 0x02 }; byte[] third = new byte[] { 0x01, 0x03 }; The method would return: first.Contains(second); // true first.Contains(third); // false second.Contains(third); // false Thanks! 回答1: you could use Jb's

问题 I have the following code in my WPF application: Task task = Task.Factory.StartNew(() => { DoInitialProcess(); }); task.ContinueWith(t => Dispatcher.BeginInvoke((Action)(() => { MessageBox.Show("Error: " + t.Exception.InnerExceptions[0].Message); })), TaskContinuationOptions.OnlyOnFaulted); It successfully triggers the continuation and displays the message box if an exception occurs, but it does not block input on the main UI thread. Why doesn't it block the main UI thread, and what is the

问题 I know that the question may not make sense, and I'm having a tough time trying to think of a way to explain it, so I will show a snippet of code to help. I'm using Winforms on visual studio express 2010: private void button1(object sender, EventArgs e) { txtOutput.Text += "Auto-collecting variables. This may take several minutes"; string v = foo(); txtOutput.Text += "\n" + v; string b = bar(); txtOutput.Text += "\n" + b; txtOutput.SelectionStart = txtOutput.Text.Length; txtOutput

问题 This is a sister question along with my first question Allow C# application built with .NET 2.0 to run on .NET 4.0/4.5. I simplified my situation a little bit there for understanding. Actually our case is a little special. Basically we wrote a C# DLL (Let's call E.dll ) for our MSI installer. Since our MSI installer is using older version of windows installer, it could not use C# DLL directly and it could only work with C type DLL, so we use an open source library called DLLExporter to

问题 For the following piece of code (.NET v4.0.30319) I am getting a null reference exception indicated below in the second continuation. Most interestingly this issue has only occurred in machines with 8GB RAM but other users have 16GB and more and they haven't reported any issue, and it is a very intermittent issue which leads me to suspect a garbage collection issue. The GetData() can be called multiple times so the first continuation of _businessObjectTask will only be called once as

问题 Compiling a VS 2010 c# project (.NET 4.0, any CPU, allow unsafe code = checked) we are getting a variety of compile errors as below: Operator '*' cannot be applied to operands of type 'System.IntPtr' and 'int' Constant value '325486741' cannot be converted to a 'int' (use 'unchecked' syntax to override) Cannot convert type 'string' to 'char*' Cannot implicitly convert type 'long' to 'byte*'. An explicit conversion exists (are you missing a cast?) Invalid expression term 'ref' All these are

问题 Compiling a VS 2010 c# project (.NET 4.0, any CPU, allow unsafe code = checked) we are getting a variety of compile errors as below: Operator '*' cannot be applied to operands of type 'System.IntPtr' and 'int' Constant value '325486741' cannot be converted to a 'int' (use 'unchecked' syntax to override) Cannot convert type 'string' to 'char*' Cannot implicitly convert type 'long' to 'byte*'. An explicit conversion exists (are you missing a cast?) Invalid expression term 'ref' All these are

问题 Compiling a VS 2010 c# project (.NET 4.0, any CPU, allow unsafe code = checked) we are getting a variety of compile errors as below: Operator '*' cannot be applied to operands of type 'System.IntPtr' and 'int' Constant value '325486741' cannot be converted to a 'int' (use 'unchecked' syntax to override) Cannot convert type 'string' to 'char*' Cannot implicitly convert type 'long' to 'byte*'. An explicit conversion exists (are you missing a cast?) Invalid expression term 'ref' All these are

问题 I am trying to run a console application from a mapped drive (T:\ is a mapped drive for a shared network folder) and get the error: The system cannot find the path specified. Why do I get this error? The administrator credentials are correct. var password = new SecureString(); password.AppendChar(Convert.ToChar("P")); password.AppendChar(Convert.ToChar("a")); password.AppendChar(Convert.ToChar("a")); password.AppendChar(Convert.ToChar("s")); Process.Start(@"t:\ca\test.exe"), "",