Archives: FAQs

Holds Syncfusion FAQs and specific data

How can I copy a bitmap from the clipboard to a PictureBox?

This code snippet shows how you can set your PictureBox’s image to be the image from the clipboard: [C#] this.pictureBox1.Image = (Bitmap)Clipboard.GetDataObject().GetData(DataFormats.Bitmap); [VB.Net] Me.pictureBox1.Image = CType(Clipboard.GetDataObject().GetData(DataFormats.Bitmap), Bitmap)

How can I programmatically create a bitmap

Since .NET uses it’s own format that is not compatible with the EnhancedMetafile format you will have to use reflection to achieve this. (From a posting in the microsoft.public.dotnet.framework.drawing newsgroup) [C#] using System.Runtime.InteropServices; using System.Reflection; public const uint CF_METAFILEPICT = 3; public const uint CF_ENHMETAFILE = 14; [DllImport(‘user32.dll’, CharSet=CharSet.Auto, ExactSpelling=true)] public static extern bool OpenClipboard(IntPtr hWndNewOwner); [DllImport(‘user32.dll’, CharSet=CharSet.Auto, ExactSpelling=true)] public static extern bool CloseClipboard(); [DllImport(‘user32.dll’, CharSet=CharSet.Auto, ExactSpelling=true)] public static extern IntPtr GetClipboardData(uint format); [DllImport(‘user32.dll’, CharSet=CharSet.Auto, ExactSpelling=true)] public static extern bool IsClipboardFormatAvailable(uint format); //Pasting into PictureBox if (OpenClipboard(this.Handle)) { if (IsClipboardFormatAvailable(CF_ENHMETAFILE)) { IntPtr ptr = GetClipboardData(CF_ENHMETAFILE); if (!ptr.Equals(new IntPtr(0))) { Metafile metafile = new Metafile(ptr,true); //Set the Image Property of PictureBox this.pictureBox1.Image = metafile; } } CloseClipboard(); }

How can I drag and drop an image from one PictureBox to another?

The following code snippet demonstrates how you can drag and copy an image from one picturebox (Source) another (Target: [C#] //In the Form Load //Set AllowDrop of the Target PictureBox to true as this property cannot be set in the Designer this.pictureBox2.AllowDrop = true; //Source PictureBox private void pictureBox1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e) { if (e.Button == MouseButtons.Left) pictureBox1.DoDragDrop( pictureBox1.Image, DragDropEffects.All ); } //Target PictureBox //Drag Drop Effects private void pictureBox2_DragEnter(object sender, System.Windows.Forms.DragEventArgs e) { if ( e.Data.GetDataPresent( DataFormats.Bitmap ) ) { e.Effect = DragDropEffects.Copy; } else e.Effect = DragDropEffects.None; } //Set the image to be the dragged image. private void pictureBox2_DragDrop(object sender, System.Windows.Forms.DragEventArgs e) { if ( (e.Data.GetDataPresent(DataFormats.Bitmap))) { this.pictureBox1.Image = (Bitmap)(e.Data.GetData(DataFormats.Bitmap)); } } [VB.NET] ’In the Form Load ’Set AllowDrop of the Target PictureBox to true as this property cannot be set in the Designer Me.pictureBox2.AllowDrop = True ’Source PictureBox Private Sub pictureBox1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) If e.Button = MouseButtons.Left Then pictureBox1.DoDragDrop(pictureBox1.Image, DragDropEffects.All) End If End Sub ’Target PictureBox ’Drag Drop Effects Private Sub pictureBox2_DragEnter(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) If e.Data.GetDataPresent(DataFormats.Bitmap) Then e.Effect = DragDropEffects.Copy Else e.Effect = DragDropEffects.None End If End Sub ’Set the image to be the dragged image. Private Sub pictureBox2_DragDrop(ByVal sender As Object, ByVal e As System.Windows.Forms.DragEventArgs) If (e.Data.GetDataPresent(DataFormats.Bitmap)) Then Me.pictureBox1.Image = CType((e.Data.GetData(DataFormats.Bitmap)), Bitmap) End If End Sub

In a debug build, how do I write debug information to the output window (similar to the TRACE macro from VC6)

You can use the Console.Write and Console.WriteLine methods from within a Windows Forms project to do this. The class DefaultTraceListener is used to implement this functionality. When your application is launched from the VS.NET IDE in Debug mode, you will see all trace and debug messages in the Output window by calling: System.Diagnostics.Trace.WriteLine() or System.Diagnostics.Debug.WriteLine()