Windows Forms General FAQ

Question

This material should not be considered as a complete coverage of the frequently asked questions, but it tries to capture the high-level features with some depth in the Windows Forms General areas.

 

1. TREEVIEW

1.1   How to retain an expanded state after reloading TreeView?

1.2   How to show hierarchical data in TreeView?

1.3   How do I implement Drag and Drop support between two TreeViews?

1.4   How to hide CheckBoxes for child nodes when CheckBoxes is set to true.

2. TEXTBOX

2.1   How do I programmatically position the cursor on a given line and character in a RichTextBox?

2.2   How to save RTF-formatted data from a Windows Forms RTF control to SQL Server?

2.3   How to get the current character’s color of a RichTextBox?

2.4   How to make the scroll smoother in a RichTextBox?

2.5   If a rich text box contains images and text, is it possible to detect when an image is clicked?

2.6   How to make a TextBox only accept digits?

3. COMBOBOX

3.1   How do I setup a ComboBox to bind to a Lookup table?

3.2   How to add a ‘please select’ item toComboBox?

3.3   How to make the drop down part of the combo box wide enough to see all items?

4. LISTBOX

4.1   How to display tooltip on individual items in a ListBox?

4.2   How to add a business object to the item collection of a ListBox and display expected text?

4.3   How to do a dual Listbox?

5. MENUSTRIP

5.1   What’s the relationship between MainMenu and MenuStrip?

5.2   How do I disable the MenuStrip's ALT-key action?

5.3   How to set the count of items displayed in a MenuStripItem’sDropDown list?

6. TOOLSTRIP

6.1   How to set the height of ToolStrip and ToolStripItem?

6.2   How to make a ToolStripTextBox hide true text and replace them with '*'?

6.3   Why a ToolStripButton didn’t cause the validation?

7. TABPAGE

7.1   How to put a close button on TabPage header?

7.2   How to hide the header of TabPage?

8. WINDOWS 7 TASKBAR

8.1   How to show two forms on Windows 7 taskbar with different labels?

8.2   How to customize the Windows 7 taskbar thumbnail picture in myapplication?

8.3   How to add an overlay icon for my application in Windows 7 taskbar?

8.4   How to show progress indicator on Windows 7 taskbar for my application?

9. BUTTON

9.1   How to add a shield icon to a button and start a process elevated?

Answer 1

1.1 How to retain an expanded state after reloading TreeView?

 

That's going to be difficult. Other parent nodes might have been expanded. Capturing the entire state of the tree is tough. The need to refresh the entire tree is odd. You can just refresh the node contents of the existing tree. You could use the TreeNode. Tag property to retain some kind of reference to the source data.

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2203734&SiteID=1

Answer 2

1.2 How to show hierarchical data in TreeView?

 

First you should create all tree nodes using these records, and then you can use a hash table to store these tree nodes. Finally loop through the hash table and add these tree nodes hierarchically.

RelatedThread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1774847&SiteID=1

Answer 3

1.3 How do I implement Drag and Drop support between two TreeViews?

 

In a posting in the Microsoft.Windows.Forms newsgroup, Brian Roder (Microsoft) gives VB.Net code snippets to handle the DragEnter, ItemDrag and DragDrop events that provide a solution to this problem. Here are some sample handlers written in C#.

Code Block

  private void treeView2_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)

  {

      TreeNode newNode;

      if (e.Data.GetDataPresent("System.Windows.Forms.TreeNode", false))

      {

          Point pt;

          TreeNode destinationNode;

          pt = treeView2.PointToClient(new Point(e.X, e.Y));

          destinationNode = treeView2.GetNodeAt(pt);

          newNode = (TreeNode)e.Data.GetData("System.Windows.Forms.TreeNode");

          if (!destinationNode.Equals(newNode))

          {

              //destinationNode.Nodes.Add(newNode.Clone());

              destinationNode.Nodes.Add((TreeNode)newNode.Clone());

              destinationNode.Expand();

              //Remove original node

              newNode.Remove();

           }

       }

   }

 

  private void treeView2_DragEnter(object sender, System.Windows.Forms.DragEventArgs e)

  {

     e.Effect = DragDropEffects.Move;

  }

 

  private void treeView2_ItemDrag(object sender, System.Windows.Forms.ItemDragEventArgs e)

  {

     DoDragDrop(e.Item, DragDropEffects.Move);

  }

Answer 4

1.4 How to hide CheckBoxes for child nodes when CheckBoxes is set to true.

 

To enable this feature, we should owner draw the tree node. We can set the TreeView.DrawMode property to OwnerDrawAll and handle the DrawNode event. Try something like the following in this handler.

Code Block

  private void treeView_DrawNode(object sender, DrawTreeNodeEventArgs e)

  {

     if (IsThirdLevel(e.Node))

     {

         Color backColor, foreColor;

 

          if ((e.State&TreeNodeStates.Selected) == TreeNodeStates.Selected)

          {

             backColor = SystemColors.Highlight;

             foreColor = SystemColors.HighlightText;

          }

         else if ((e.State&TreeNodeStates.Hot) == TreeNodeStates.Hot)

         {

              backColor = SystemColors.HotTrack;

              foreColor = SystemColors.HighlightText;

          }

          else

          {

              backColor = e.Node.BackColor;

              foreColor = e.Node.ForeColor;

          }

 

          using (SolidBrush brush = newSolidBrush(backColor))

          {

              e.Graphics.FillRectangle(brush, e.Node.Bounds);

          }

 

          TextRenderer.DrawText(e.Graphics, e.Node.Text,this.treeView.Font, e.Node.Bounds, foreColor, backColor);

 

          if ((e.State&TreeNodeStates.Focused) == TreeNodeStates.Focused)

          {

              ControlPaint.DrawFocusRectangle(e.Graphics, e.Node.Bounds,foreColor, backColor);

           }

 

          e.DrawDefault = false;

      }

      else

      {

          e.DrawDefault = true;

       }

  }

 

  private static bool IsThirdLevel(TreeNode node)

  {

      return node.Parent != null&&node.Parent.Parent != null;

   }

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1883238&SiteID=1

Answer 5

2.1 How do I programmatically position the cursor on a given line and character in a RichTextBox?

 

The RichTextBox control contains a Lines array property, one entry for every line. Each line entry has a Length property. With this information, you can position the selection cursor using code such as:

Code Block

  private void GoToLineAndColumn(RichTextBoxrtb, int line, int column)

  {

      rtb.Focus();

      if (line < 0 || column < 0)

      {

          rtb.SelectionStart = 0;

      }

      else

      {

          if (line >rtb.Lines.Length - 1)

          {

              rtb.SelectionStart = rtb.GetFirstCharIndexFromLine(rtb.Lines.Length - 1)
                      + rtb.Lines[rtb.Lines.Length - 1].Length;

          }

          else

          {

              int firstCharIndexOfline = rtb.GetFirstCharIndexFromLine(line);

              int textlengthOfline;

              textlengthOfline = rtb.Lines[line].Length;

              if (column >textlengthOfline)

              {

                  column = textlengthOfline;

                  rtb.SelectionStart = firstCharIndexOfline + column;

               }

          }

    }

Answer 6

2.2 How to save RTF-formatted data from a Windows Forms RTF control to SQL Server?

 

In this situation, using a RichTextBox is the easiest way; we can just bind the field to the Rtf property of RichTextBox.

Code Block

  Binding bd =new Binding("Rtf", dt, "descs",true);

 

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2246017&SiteID=1

Answer 7

2.3 How to get the current character’s color of a RichTextBox?

 

The RichTextBox has provided you a property named SelectionColor; you can use this property to get the current character’s color

Code Block      

 private void richTextBox1_MouseMove(object sender, MouseEventArgs e)

 {

      int index = richTextBox1.GetCharIndexFromPosition(e.Location);

      richTextBox1.SelectionStart = index;

      label1.Text = richTextBox1.SelectionColor.ToString();

 }

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2139967&SiteID=1

Answer 8

2.4 How to make the scroll smoother in a RichTextBox?

 

Try to use two windows API functions, GetScrollPos and PostMessage. The GetScrollPos is used to get the current position of RichTextBox, and the PostMessage is used to place a scroll-down message in the message queue associated with the thread that created the window.

Code Block

<Runtime.InteropServices.DllImport("user32.dll", EntryPoint:="PostMessage")> _

 PublicSharedFunction PostMessage(ByValhwndAsInteger, ByValwMsgAsInteger, ByValwParamAsInteger, ByVallParamAsInteger) AsInteger

 EndFunction

<Runtime.InteropServices.DllImport("user32.dll", EntryPoint:="GetScrollPos")> _

 PublicSharedFunction GetScrollPos(ByValhwndAsInteger, ByValnBarAsInteger) AsInteger

 EndFunction

 PublicConst WM_VSCROLL AsInteger = 277

 PublicConst SB_THUMBPOSITION AsInteger = 4

 PublicConst SBS_VERT AsInteger = 1

 

 Private previousPos AsInteger = 0 

 PrivateSub RTBAutoScroll_Load(ByVal sender AsObject, ByVal e AsEventArgs) HandlesMyBase.Load

     Me.RichTextBox1.[Select](0, 0)

     Me.RichTextBox1.ScrollToCaret()

     Me.Timer1.Interval = 300

     AddHandlerMe.Timer1.Tick, AddressOf timer1_Tick

 

     Dim td AsNewDateTime()

     Me.Text = td.ToString()

 EndSub

 

 PrivateSub timer1_Tick(ByVal sender AsObject, ByVal e AsEventArgs)

    Dim currentPos AsInteger = GetScrollPos(CInt(Me.richTextBox1.Handle), SBS_VERT)

    If previousPos<>currentPos Or Else currentPos = 0 Then

        previousPos = currentPos

        PostMessage(CInt(Me.richTextBox1.Handle), WM_VSCROLL, SB_THUMBPOSITION + 65536 * (currentPos + 1), 0)

    EndIf

 EndSub

 

 PrivateSub Button1_Click_1(ByVal sender AsSystem.Object, ByVal e AsSystem.EventArgs) Handles Button1.Click

    If Button1.Text = "Auto Scroll"Then

        Button1.Text = "Pause"

        Timer1.Enabled = True

    Else If Button1.Text = "Pause" Then

        Button1.Text = "Auto Scroll"

        Timer1.Enabled = False

    EndIf

      EndSub

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2102412&SiteID=1

Answer 9

2.5 If a rich text box contains images and text, is it possible to detect when an image is clicked?

 

The Rich Text Format (RTF) Specification says, pictures are destinations, and begin with the \pict control word. We can try to judge the SelectedRtf string to see if this contains the \pict when click on the RichTextBox.

Code Block

  this.richTextBox1.MouseClick += new MouseEventHandler(richTextBox1_MouseClick);

 

     void richTextBox1_MouseClick(object sender, MouseEventArgs e)

     {

         if (this.richTextBox1.SelectedRtf.IndexOf(@"\pict") != -1 &&
            this.richTextBox1.SelectionType == RichTextBoxSelectionTypes.Object)

         {

            MessageBox.Show("Image has been clicked!");

         }

}

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2191267&SiteID=1

Answer 10

2.6 How to make a TextBoxonly accept digits?

 

You can handle the textbox's KeyPress event and if the char passed in is not digits, mark the events argument as showing that the character has been handled. Below is a derived TextBox that only accepts digits (and control characters such as backspace).

Code Block

public class NumbersOnlyTextBox : TextBox

{

 protected override void OnKeyPress(KeyPressEventArgs e)

 {

      base.OnKeyPress(e);

      if (!(char.IsDigit(e.KeyChar) || char.IsControl(e.KeyChar)))

{

          e.Handled = true;

       }  

          }

}

Answer 11

3.1 How do I setup a ComboBox to bind to a Lookup table?

 

A common use of a ComboBox in a data bound application is as a lookup based UI control.  From a database perspective, a Lookup control is used to provide the “lookup” values for a foreign key.  For example, assume you have a customer table with a “StateID” where the “StateID” is a foreign key into a “States” table.  From a UI perspective, you’d like to allow the user to select a State via a ComboBox.  To do this, you use Complex Binding to bind the ComboBox to the States table (setting the ComboBox.DisplayMember and ComboBox.ValueMember) and use Simple List Binding to bind the ComboBoxSelectedValue to the Customer “StateID”.

Code Block

  Customer cust = new Customer("Joe", "WA");

  this.statesCB.DisplayMember = "Name";

  this.statesCB.ValueMember = "Code";

  this.statesCB.DataSource = statesTable;

  this.statesCB.DataBindings.Add("SelectedValue", cust, "StateID", true);

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1753655&SiteID=1

Answer 12

3.2 How to add a ‘please select’ item to ComboBox?

 

If the ComboBox is not data bound, you can add an item to the item collection.

Code Block

  this.comboBox1.Items.Insert(0, "please select");

this.comboBox1.SelectedIndex = 0; 

If the ComboBox is data bound, you will need to add this item to the data source

Code Block

  Customer cust = new Customer("Joe", null);

     

  DataRow row = statesTable.NewRow();

  row["Name"] = " please select";

  row["Code"] = DBNull.Value;

  statesTable.Rows.Add(row);

 

  this.statesCB.DisplayMember = "Name";

  this.statesCB.ValueMember = "Code";

  this.statesCB.DataSource = statesTable;

  this.statesCB.DataBindings.Add("SelectedValue", cust, "StateID", true); 

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1769727&SiteID=1

Answer 13

3.3 How to make the drop down part of the combo box wide enough to see all items?

 

You can set the DropDownWidth of a combo box to make the combo box dropdown wide enough.

Code Block

  string s = "this is a really, really, really, really, really, long string";

  Graphics g = Graphics.FromHwnd(this.Handle);

  Size size = g.MeasureString(s, comboBox1.Font);

  comboBox1.DropDownWidth = Convert.ToInt32(size.Width);

  this.comboBox1.Items.Add(s);

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2281333&SiteID=1

Answer 14

4.1 How to display tooltip on individual items in a ListBox?

 

If you want to display tooltip on individual items in a ListBox, here is a quick easy way. First create a method to handle mouse move events, and then hook it to the MouseMove event of the ListBox. You will also need a ToolTip object as a member variable for the form. The code required to create and update the tooltip is:

Code Block

  private void onMouseMove(object sender, MouseEventArgs e)

  {

     if (sender isListBox)

     {

         ListBox listBox = (ListBox)sender;

         Point point = new Point(e.X, e.Y);

         int hoverIndex = listBox.IndexFromPoint(point);

         if (hoverIndex>= 0 &&hoverIndex<listBox.Items.Count)

         {

             tt.SetToolTip(listBox, listBox.Items[hoverIndex].ToString());

          }

      }

   }

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2073944&SiteID=1

Answer 15

4.2 How to add a business object to the item collection of a ListBox and display expected text?

The most common way to achieve this is to set the DiaplayMember to the Proterty name of your business object.

The second way is to use a TypeConverter to convert the business object. You need to custom a TypeConverter and override its ConvertTo method. Check the following sample code.

Code Block

[TypeConverter(typeof(BusinessTypeConvert))]

Class BusinessObject

{

 int id;

 

 public int Id

 {

     get { return id; }

     set { id = value; }

}

 

 string name;

 

 public string Name

 {

     get { return name; }

     set { name = value; }

  }

}

 

Class BusinessTypeConvert :TypeConverter

{

 public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)

{

    if (destinationType == typeof(string))

{

            return ((BusinessObject)value).Name;

     }

 

     return base.ConvertTo(context, culture, value, destinationType);

  }

}

The third choice is to override the ToString method of your business object and return the expected text in this method. But this is not recommended since ToString method is usually used to return some information about the class.

Answer 16

4.3 How to do adualListbox?

 

I want to use two buttons to move items back and forth. For example, ‘L->R’ moves items from left ListBox to right ListBox, ‘R->L’ moves items form right ListBox to left ListBox.

Place two ListBoxes with two buttons between them. One button with Text ‘R->L’, and the other ‘L->R’.

In the L->R click event handler:

Code Block

  foreach (int index in listBox1.SelectedIndices)

  {

      listBox2.Items.Add(listBox1.Items[index]);

      listBox1.Items.RemoveAt(index);

}

 

In the R-L click event handler:

Code Block

  foreach (int index in listBox2.SelectedIndices)

  {

      listBox1.Items.Add(listBox2.Items[index]);

      listBox2.Items.RemoveAt(index);

}

For both ListBoxes, the property SelectionMode should be set to MultiSimple. And place several items in one or both of the ListBoxes

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1830319&SiteID=1

Answer 17

5.1 What’s the relationship betweenMainMenu and MenuStrip?

 

MenuStrip is a complete replacement for MainMenu and has nothing in common with that control.  The old MainMenu was built on top of the built-in Windows support for menus.  The GetClientRect() API function automatically deducts the menu size from the client rectangle.  MenuStrip doesn't use Windows menus, thus GetClientRect() returns the size of the window's client area, disregarding the space taken up by the MenuStrip.  The same is true for any other window edge adornments like StatusStrip and ToolStrip, or any docked panels for that matter.

Answer 18

5.2 How do I disable the MenuStrip's ALT-key action?

 

Just override the ProcessDialogKey in your form, as:

Code Block

  protected override bool ProcessDialogKey(Keys keyData)

  {

      if ((keyData&Keys.Alt) == Keys.Alt)

      {

return true;

       }               

      else

      {

          return base.ProcessDialogKey(keyData);

       }

    }

Answer 19

5.3 How to set the count of items displayed in a MenuStripItem’sDropDown list?

If there are too many items in MenuStripItem’s item collection, it will use a lot of space to show these menus. I want to show only eight (or other number) menus. How can I achieve this?

We will need to set the AutoSize of the MenuStripItem’sDropDown portion to false and inputs its height.

Code Block

  this.fileToolStripMenuItem.DropDown.AutoSize = false;

  this.fileToolStripMenuItem.DropDown.Height = 200;

Answer 20

6.1 How to set the height of ToolStrip and ToolStripItem?

 

Try to set both ToolStrip and ToolStripItem’s AutoSize to false, and make sure your ToolStrip’s height is greater than all your ToolStripItems. Try something like the following:

Code Block

  this.toolStrip1.AutoSize = false;

  this.toolStripButton1.AutoSize = false;

  this.toolStripButton2.AutoSize = false;

  this.toolStripButton3.AutoSize = false;

  this.toolStripButton1.Height = 20;

  this.toolStripButton2.Height = 40;

  this.toolStripButton3.Height = 60;

  this.toolStrip1.Height = 65; 

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2080536&SiteID=1

Answer 21

6.2 How to make a ToolStripTextBox hide truetext and replace them with '*'?

 

The ToolStripTextBox actually contains a TextBox and use this TextBox to allow the user to type in. You can get the TextBox hosted in the ToolStripTextBox and set the PasswordChar property.

Code Block

  if (this.toolStripTextBox1.Control isTextBox)

  {

      TextBox tb = this.toolStripTextBox1.Control asTextBox;

      tb.PasswordChar = '*';

   }

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2042939&SiteID=1

Answer 22

6.3 Why a ToolStripButtondidn’tcause the validation?

 

By default, toolbars and menus do not need focus when you click on it, thus it does not force validation for controls. A related question is that why it didn’t commit the data to the database when clicking on a toolstrip. To solve this problem, add the following line of code in the click event to force the validation.

Code Block

  this.Validate();//this refers to your form

Answer 23

7.1 How to put a close button on TabPage header?

 

We can build a custom TabControl and override its OnDrawItem method in which you paint the "close button", then do the hit testing and close the tab when the "close button" is clicked. The following article demonstrates the idea in more detail:

http://www.codeproject.com/cs/miscctrl/firefoxtabcontrol.asp

Answer 24

7.2 How to hidethe header of TabPage?

 

Add a new class to your project, paste the code shown below and build the project.  You can now drop the control from the top of the toolbox onto your form.  At design time, the control looks like a regular TabControl.  At run-time, you only see the pages.  Use the SelectedIndex property to step through the pages.

Code Block

using System;

using System.Windows.Forms;

 

public class WizardPages : TabControl

{

 protected override void WndProc(ref Message m)

 {

     // Hide tabs by trapping the TCM_ADJUSTRECT message

     if (m.Msg == 0x1328 && !DesignMode)

{

m.Result = (IntPtr)1;

}

     else

     {

           base.WndProc(ref m);

      }

          }

  }

Related Thread:
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1518961&SiteID=1

Answer 25

8.1 How to showtwo forms on Windows 7 taskbar with different labels?

 

You can make use of the Microsoft Windows API Code Pack to make this easier.

The basic idea is to call the SetApplicationIdForSpecificWindow method of the TaskbarManager class to set different application IDs for different forms. If two forms have different application IDs, they will be grouped in different labels on the taskbar.TaskbarManager.Instance.SetApplicationIdForSpecificWindow(
subForm.Handle, SubFormAppID);

You can find the complete sample in All-In-One Code Framework, the project name is“CSWin7AppID”.

Download: http://1code.codeplex.com/releases/view/41170#DownloadId=108690

Answer 26

8.2 How to customize the Windows 7 taskbar thumbnail picture in my application?

 

The Microsoft API Code Pack can help on this. Construct a TabbedThumbnail which takes a window handle and a control as parameters, and then call the AddThumbnailPreview method of the TabbedThumbnailManager class to add a thumbnail for the current application.You can also get or remove the thumbnails by calling the GetThumbnailPreview and the RemoveThumbnailPreview method.

 

Another type of customization onthumbnails is adding buttons to it for custom actions. The corresponding class is ThumbnailToolbarButton. You can call the AddButtons method of the ThumbnailToolbarManager class to add buttons to a thumbnail.

 

You can find the complete sample in All-In-One Code Framework, the project name is“CSWin7TaskbarThumbnail”.

 

Download: http://1code.codeplex.com/releases/view/41170#DownloadId=108690

Answer 27

8.3 How to add an overlay icon for my application in Windows 7 taskbar?

 

You can make use of the Microsoft Windows API Code Pack to make this easier. To set an overlay icon, use the TaskbarManager.SetOverlayIcon method.

For example:

// Set the Taskbar Overlay Icon
// TaskbarManager.SetOverlayIcon(Icon icon, string accessibilityText);
TaskbarManager.Instance.SetOverlayIcon(Properties.Resources.Available, "Available icon");

 

 

 

Note that before using this feature, we need to check whether the current Windows version supports this feature by using code below:

if (!TaskbarManager.IsPlatformSupported)
{
// If current system doesn’t support this, do something else.
}

The All-In-One Code Framework has two samples “CSWin7TaskbarOverlayIcons” and “VBWin7TaskbarOverlayIcons” showing how to do this.

You can download the samples here:

http://1code.codeplex.com/releases/view/41170

 

Related Threads:

Windows API Code Pack for the Microsoft .NET Framework

http://msdn.microsoft.com/en-us/magazine/dd942846.aspx#id0420051

Answer 28

8.4 How to show progress indicator on Windows 7 taskbar for my application?

 

You can use the TaskbarManager class available in the Microsoft Windows API Code Pack to do this. The SetProgressState method and the SetProgressValue method modify the state of the taskbar progress bar. There are several states available for applications to use: indeterminate, paused, error and normal.

 

For example:

// Set the Taskbar button Progress Bar state
// TaskbarManager.SetProgressState(TaskbarProgressBarState state)
TaskbarManager.Instance.SetProgressState(TaskbarProgressBarState.Paused);

 

// Set the Taskbar button Progress Bar value
// TaskbarManager.SetProgressValue(int currentValue, int maximumValue)
TaskbarManager.Instance.SetProgressValue(progressBar.Value, MAX_PROGRESSBAR_VALUE);

 

 

 

Note that before using this feature, we need to check whether the current Windows version supports this feature by using this code:

if (!TaskbarManager.IsPlatformSupported)
{
// If current system doesn’t support this, do something else.
}

The All-In-One Code Framework has two samples “CSWin7TaskbarProgressbar” and “VBWin7TaskbarProgressbar” showing how to do this.

You can download the samples here:

http://1code.codeplex.com/releases/view/41170

 

Related Threads:

Windows API Code Pack for the Microsoft .NET Framework

http://msdn.microsoft.com/en-us/magazine/dd942846.aspx#id0420051

Answer 29

9.1How to add a shield icon to a button and start a process elevated?

 

The All-In-One Code Framework has two samples “ CSUACSelfElevation” and “VBUACSelfElevation” demonstrate how to check if the application is running asadministrator. A shield icon will be added to a button on the UI if the application is not run as administrator.

 

The sample uses WindowsIdentity class to check the account the process is running under. It calls SendMessage to add a shield icon to the button if the process is not running asadministrator. For more information, please refer to ReadMe.txt included in the sample.

 

You can download the All-In-One Code Framework samples here:

http://1code.codeplex.com/wikipage?title=All-In-One%20Code%20Framework%20Examples&ProjectName=1code