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OleDb / OleDbConnection resizing form (bug?)

Can someone help with a problem I can't seem to resolve. I have created a C# form in both VSE2012 express for desktop and VSE2013 express for Desktop, where i have left the form the default size and added one button again totally default. The button is coded to open and close a db connection.
When the button is clicked the form and its contents all shrink by about 25%, i have tried all the default setting with no joy. I even substituted the access db file for a text file and it still happens. Tried this on both window 7 and 8.1
Form1.cs (all the code)
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Data.OleDb;
namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
OleDbConnection myConn = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;"
+ #"Data Source="
+ #"..\..\..\x.accdb");
private void button1_Click(object sender, EventArgs e)
{
try
{
myConn.Open();
myConn.Close();
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
}
}
Uneditted Form1.Designer.cs
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.button1 = new System.Windows.Forms.Button();
this.SuspendLayout();
//
// button1
//
this.button1.Location = new System.Drawing.Point(106, 138);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(75, 23);
this.button1.TabIndex = 0;
this.button1.Text = "button1";
this.button1.UseVisualStyleBackColor = true;
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(8F, 16F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(282, 253);
this.Controls.Add(this.button1);
this.Name = "Form1";
this.Text = "Form1";
this.ResumeLayout(false);
}
#endregion

This must be a OleDb or .NET bug. It is only noticeable on very high resolution screens and the simple act of calling OleDb.OleDbConnection.Open causes the form to ignore any DPI or Font scaling.
I've tried moving the call to open the OleDb to a separate class and also to a separate DLL but the results are always the same.
A user posted an example on YouTube here: https://www.youtube.com/watch?v=zdby6gmbX_4
I guess we'll just need to report it to MS
***** Found a way to fix it
If you uninstall the "Microsoft Access Database Engine 2010 Redistributable" 32 bit version and then install the 64 bit version. You then uninstall the 64 bit version and then reinstall the 32 bit version it will now work

Dynamic creation of forms & containers

I'm very new to C#.
Below is a code that I'm trying to create forms and containers within the code; but I've problems with it.
I start with a new Windows Forms Application template.
I change the Program.cs file a little, so that I'd be able to create the FormMain dynamically.
When the lines Container.Add(BtnClose) and BtnClose_Setup() in FormMain.cs are commented, the code compile and run. However, there are still some weird results in the program.
(a) The form FormMain is supposed to show up at (20, 20) (upper left corner), as the FormMain_Setup says; but when I run the app, though width & height settings show up as expected (800, 600), the upper left corner changes every time (does not stick to 20, 20).
(b) The esc key works as expected and closes the form and application.
When the lines Container.Add(BtnClose) and BtnClose_Setup() in FormMain.cs are not commented, the code compile but VS sends me a message when it's run: "An unhandled exception of type 'System.TypeInitializationException' occurred in mscorlib.dll"
Can someone tell me what I'm doing wrong?
Program.cs file:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace test {
static class Program {
public static FormMain FormMain = new FormMain();
[STAThread]
static void Main() {
Application.Run(FormMain);
}
}
}
FormMain.cs file:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace test {
public partial class FormMain : Form {
Button BtnClose = new Button();
public void BtnClose_Setup() {
BtnClose.Text = "Ok";
BtnClose.Top = 500;
BtnClose.Left = 700;
}
public void FormMain_Setup() {
Top = 20;
Left = 20;
Width = 800;
Height = 600;
KeyDown += FormMain_KeyDown;
//Container.Add(BtnClose);
//BtnClose_Setup();
}
void FormMain_KeyDown(object sender, KeyEventArgs e) {
if(e.KeyCode == Keys.Escape) {
Close();
}
}
public FormMain() {
InitializeComponent();
FormMain_Setup();
}
}
}

Call Controls.Add(BtnClose); instead of Container.Add(BtnClose);.
As for fixing the form position: set StartPosition = FormStartPosition.Manual; property.
To properly close the form on Esc, override ProcessCmdKey method:
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
if (keyData == Keys.Escape)
{
Close();
return true;
}
return base.ProcessCmdKey(ref msg, keyData);
}

By default a forms StartPosition is set to WindowsDefaultLocation. You need to set it to Manual; either in the designer or in the code.
To add a control to a form, you want to add it to the form's Controls collection, not the Container.
Also, if you want the form to continue to get KeyDown events after the button is added you need to set KeyPreview to true.
public void FormMain_Setup()
{
StartPosition = FormStartPosition.Manual;
KeyPreview = true;
Top = 20;
Left = 20;
Width = 800;
Height = 600;
KeyDown += FormMain_KeyDown;
Controls.Add(BtnClose);
BtnClose_Setup();
}

Tooltip that's not linked to any particular control

I'm trying to make something like a spellchecker, that will list possible words under the current caret position. I thought I would do this by creating a tooltip, moving it according to the caret's location, and changing the text inside the tooltip.
I'm having problems.
I'm trying to show the tooltip with tip.Show(form, x, y);
However, this app is running from the systray. It has no GUI elements aside from that? What do I use as the form parameter? the notifyIcon1, Form1, etc. do not work.
I would start with an example that displayed a static tooltip that moved along with my mouse cursor or something. Can someone point me in the right direction?
Thanks

You may be able to do this but not using a tooltip class as that is quite limiting, there is a fantastic tooltip helper called VXPLib, using html formatting (which I suppose would give your listing of words an edge - say in different colours). The VXPLib is a COM object (written in C++) but accessible from the .NET language and there is a wrapper that can do it for you along with code samples. I have tried them and they actually work and make it look nice...See here for more information.
Hope this helps,
Best regards,
Tom.

I posted an answer in this thread that uses a transparent, maximized for to simulate drawing a tooltip anywhere on the screen, including the desktop. Maybe it will help: Creating a tooltip from a system-tray only app
Edit: Copied the code over from the linked post for ease of reading :-)
Here you go, use a transparent, maximized form that you BringToFront() before showing the ToolTip
Form1 Code:
using System;
using System.Windows.Forms;
namespace SO_ToolTip
{
public partial class Form1 : Form
{
Random _Random = new Random();
ToolTip _ToolTip = new ToolTip();
public Form1()
{
InitializeComponent();
}
private void timer1_Tick(object sender, EventArgs e)
{
BringToFront();
_ToolTip.Show("Blah blah... Blah blah... Blah blah...", this, _Random.Next(0, Width), _Random.Next(0, Height), 10000);
}
}
}
Form1 Designer Code: So you can see the forms properties:
namespace SO_ToolTip
{
partial class Form1
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.timer1 = new System.Windows.Forms.Timer(this.components);
this.SuspendLayout();
//
// timer1
//
this.timer1.Enabled = true;
this.timer1.Interval = 1000;
this.timer1.Tick += new System.EventHandler(this.timer1_Tick);
//
// Form1
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(284, 264);
this.ControlBox = false;
this.MaximizeBox = false;
this.MinimizeBox = false;
this.Name = "Form1";
this.Opacity = 0;
this.ShowIcon = false;
this.ShowInTaskbar = false;
this.WindowState = System.Windows.Forms.FormWindowState.Maximized;
this.ResumeLayout(false);
}
#endregion
private System.Windows.Forms.Timer timer1;
}
}
Update: With ControlBox = false; and Opacity = 0; the form is not only visually transparent but is immune to user input. That is even when the Form1 above if the top most window clicking in it's area falls through to the next window/desktop. Just as if the form wasn't there. The BringToFront() before showing the tooltip is required because otherwise the tooltip could be drawn under other windows, which is not what you want.

If there's no GUI in your application, then in what application are you to providing a spell checker?
If you are integrating your application with another existing application (even non-.NET applications), then you need to obtain the handle (HWND) of the other application and convert it to a System.Windows.Forms.IWin32Window. Once you do this, you can use that handle as the form in the ToolTip.Show method.
Here is the code you need:
using System.Diagnostics;
//...
public class MyWindow : System.Windows.Forms.IWin32Window
{
private IntPtr _hwnd;
public IntPtr Handle
{
get
{
return _hwnd;
}
}
public MyWindow(IntPtr handle)
{
_hwnd = handle;
}
//...
public static MyWindow GetWindowFromName(string processName)
{
Process[] procs = Process.GetProcessesByName(processName);
if (procs.Length != 0)
{
return new MyWindow(procs[0].MainWindowHandle);
}
else
{
throw new ApplicationException(String.Format("{0} is not running", processName));
}
}
}
//...
tip.Show("this worked...", MyWindow.GetWindowFromName("Notepad"), 0, 0, 2000);

I have worked on creating a tooltip that is "not linked to any particular control", because I wanted to replace one of my AutoHotkey scripts which uses the ToolTip command.
I have my code stored at: https://bitbucket.org/tahir-hassan/dotnettooltip
All you do is, instantiate the control, set the text it displays, set the coordinates, and call Show method:
var tooltip = new ToolTipLib.ToolTip()
{
Text = "this is a nice toolTip",
LocationX = 100,
LocationY = 200
};
tooltip.Show();

Windows Forms Opacity After Shown- C#

I am tryig to fade-in a windows form using c# but it doesnt seem to work after I have shown the form. Is it possible to change the forms opacity after Ive shown it?
Code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Timers;
namespace ToolStrip
{
public partial class Form1 : Form
{
Form ToolForm = new ToolForm();
Form PropForm = new PropertyGrid();
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
ToolForm.FormBorderStyle = FormBorderStyle.FixedToolWindow;
ToolForm.Owner = this;
ToolForm.Show();
ToolForm.Location = new Point(50, 50);
}
private void button2_Click(object sender, EventArgs e)
{
PropForm.FormBorderStyle = FormBorderStyle.FixedToolWindow;
PropForm.Owner = this;
PropForm.Show();
PropForm.Location = new Point(50, 50);
System.Timers.Timer aTimer = new System.Timers.Timer(10000);
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = 2000;
aTimer.Enabled = true;
Console.WriteLine("Press the Enter key to exit the program.");
Console.ReadLine();
}
private void OnTimedEvent(object source, ElapsedEventArgs e)
{
PropForm.Opacity = PropForm.Opacity - 0.25;
Console.WriteLine(PropForm.Opacity);
}
}
}

because you r using System.Timers.Timer which is a multithread timer, in it's OnTimedEvent() it calls control created by another thread, which cause exception.
If you use System.Windows.Forms.Timer, it will work. i tested.

Using your code (and creating the other necessary Form classes), I get a cross-threading exception the first time the timer fires and the event handler is called, as Benny suggests.
Making changes to your code to check InvokeRequired in the timer event handler, and use Invoke if necessary to change PropForm.Opacity, results in the opacity changing after the form is shown, as required.
Note that you probably want to start with an Opacity of 0, and increase it gradually - otherwise your form will start off completely solid and gradually fade out
I will mention in passing that Opacity will have no effect on some versions of Windows, though you say you have Opacity effects working elsewhere, so it shouldn't be that in this case.

Ive gotten it to work without timers:
int Loop = 0;
for (Loop = 100; Loop >= 5; Loop -= 10)
{
this.PropForm.Opacity = Loop / 95.0;
this.PropForm .Refresh();
System.Threading.Thread.Sleep(100);
}
but i cant seem to change this example to fade-in instead of out.

C# best way to "validate" an object bound to a form

I got a business object bounds to a form (each property is bound to a control). There is some business specificatios (such as this field should not be empty, this one must be greater than 0 etc...). What is the best way to check all the rules ?
I currently have a validator on each contorl, so I can check for all validator to be ok, but I don't really like this solution. Indeed the rules are dispached and it's no easy to see all at once.
I can have a big method CheckValidaty that check for all the rules but this leads to a double check with the validators.
What would you do, other solution ?

I would suggest that let the BusinessObject implement IDataErrorInfo. I think it is the cleanest way to handle business errors.
Take a look at these links:
http://msdn.microsoft.com/en-us/library/system.componentmodel.idataerrorinfo_members.aspx
http://www.codegod.de/WebAppCodeGod/objectdatasource-and-idataerrorinfo-with-winforms-AID427.aspx

There are two kinds of validation: data-specific validation (in the persistence layer) and user-interface validation. I prefer to put validation near the input side, because generally you want to show the user what's wrong, and trying to connect data validation to the user interface adds more indirection that has to match the data binding indirection.
Putting data validation in control classes does not seem like a good idea. That basically means the control class can be used only for one specific field.
The standard Windows Forms way of doing things is to put data validation in container. That way the validation can check against the state of other properties and connect the specific control to the ErrorProvider object(s) to display a pertinent error message.
class EmployeeForm : UserControl
{
EmployeeObject employee;
// ...
void employeeNameTextBox_Validating (object sender, CancelEventArgs e)
{
if ( employee.Name.Trim ().Length == 0 ) {
errorProvider.SetError (employeeNameTextBox, "Employee must have a name");
e.Cancel = true;
}
}
void employeeHireDateControl_Validating (...)
{
if ( employee.HireDate < employee.BirthDate ) {
errorProvider.SetError (employeeHireDateControl,
"Employee hire date must be after birth date");
e.Cancel = true;
}
}
}
class ExplorerStyleInterface : ...
{
// ...
bool TryDisplayNewForm (Form oldForm, Form newForm)
{
if ( ! oldForm.ValidateChildren () )
return false;
else {
HideForm (oldForm);
ShowForm (newForm);
return true;
}
}
}
The standard WF way is to fire the Validating event for the specific control when the control loses focus or when ValidateChildren is called on the container (or the container's container). You set up a handler for this event through the event properties for the control on the container; the handler is automatically added to the container.
I'm not sure why this way isn't working for you, unless you don't like the default behavior of refusing to reliquish focus on error, which you can change by setting the AutoValidate property of the container (or the container's container) to EnableAllowFocusChange.
Tell us specifically what you don't like about the standard Windows Forms way of doing things, and maybe we can either offer alternatives or persuade you the standard way will do what you want.

If you have this situation:
- Many controls in the Winform to
validate
- A validation rule for each control
- You want an overall validation within the Save() command
- You don't want validation when controls focus changes
- You also need an red icon showing errors in each control
Then you can copy and paste the following code, that implements a Form with 2 textbox and a Save button:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace ValidationApp
{
public class ValidationTestForm : Form
{
private TextBox textBox1;
private TextBox textBox2;
private Button btnSave;
private ErrorProvider errorProvider1;
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.textBox1 = new System.Windows.Forms.TextBox();
this.textBox2 = new System.Windows.Forms.TextBox();
this.btnSave = new System.Windows.Forms.Button();
this.errorProvider1 = new System.Windows.Forms.ErrorProvider(this.components);
((System.ComponentModel.ISupportInitialize)(this.errorProvider1)).BeginInit();
this.SuspendLayout();
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(131, 28);
this.textBox1.Name = "textBox1";
this.textBox1.Size = new System.Drawing.Size(100, 20);
this.textBox1.TabIndex = 0;
//
// textBox2
//
this.textBox2.Location = new System.Drawing.Point(131, 65);
this.textBox2.Name = "textBox2";
this.textBox2.Size = new System.Drawing.Size(100, 20);
this.textBox2.TabIndex = 1;
//
// btnSave
//
this.btnSave.Location = new System.Drawing.Point(76, 102);
this.btnSave.Name = "btnSave";
this.btnSave.Size = new System.Drawing.Size(95, 30);
this.btnSave.TabIndex = 2;
this.btnSave.Text = "Save";
this.btnSave.UseVisualStyleBackColor = true;
this.btnSave.Click += new System.EventHandler(this.btnSave_Click);
//
// errorProvider1
//
this.errorProvider1.ContainerControl = this;
//
// ValidationTestForm
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(266, 144);
this.Controls.Add(this.btnSave);
this.Controls.Add(this.textBox2);
this.Controls.Add(this.textBox1);
this.Name = "ValidationTestForm";
this.Text = "ValidationTestForm";
((System.ComponentModel.ISupportInitialize)(this.errorProvider1)).EndInit();
this.ResumeLayout(false);
this.PerformLayout();
}
#endregion
public ValidationTestForm()
{
InitializeComponent();
// path validation
this.AutoValidate = AutoValidate.Disable; // validation to happen only when you call ValidateChildren, not when change focus
this.textBox1.CausesValidation = true;
this.textBox2.CausesValidation = true;
textBox1.Validating += new System.ComponentModel.CancelEventHandler(textBox1_Validating);
textBox2.Validating += new System.ComponentModel.CancelEventHandler(textBox2_Validating);
}
private void textBox1_Validating(object sender, System.ComponentModel.CancelEventArgs e)
{
if (textBox1.Text.Length == 0)
{
e.Cancel = true;
errorProvider1.SetError(this.textBox1, "A value is required.");
}
else
{
e.Cancel = false;
this.errorProvider1.SetError(this.textBox1, "");
}
}
private void textBox2_Validating(object sender, System.ComponentModel.CancelEventArgs e)
{
if (textBox2.Text.Length == 0)
{
e.Cancel = true;
errorProvider1.SetError(this.textBox2, "A value is required.");
}
else
{
e.Cancel = false;
this.errorProvider1.SetError(this.textBox2, "");
}
}
private void btnSave_Click(object sender, EventArgs e)
{
if (this.ValidateChildren()) //will examine all the children of the current control, causing the Validating event to occur on a control
{
// Validated! - Do something then
}
}
}
}
Note:
textBox1_Validating, textBox2_Validating...do the rule check

What is wrong with the validator approach? It's quite acceptable, and you can write your own, to implement your own rules.