using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Windows.Forms;
class ImageDrop : Form {
bool bIsTarget;
Image image;
public static void Main() {
Application.Run(new ImageDrop());
}
public ImageDrop() {
AllowDrop = true;
}
protected override void OnDragOver(DragEventArgs dea) {
if (dea.Data.GetDataPresent(DataFormats.FileDrop) || dea.Data.GetDataPresent(typeof(Metafile)) || dea.Data.GetDataPresent(typeof(Bitmap))) {
if ((dea.AllowedEffect & DragDropEffects.Move) != 0)
dea.Effect = DragDropEffects.Move;
if (((dea.AllowedEffect & DragDropEffects.Copy) != 0) && ((dea.KeyState & 0x08) != 0)) // Ctrl key
dea.Effect = DragDropEffects.Copy;
}
}
protected override void OnDragDrop(DragEventArgs dea) {
if (dea.Data.GetDataPresent(DataFormats.FileDrop)) {
string[] astr = (string[])dea.Data.GetData(DataFormats.FileDrop);
image = Image.FromFile(astr[0]);
Invalidate();
} else {
if (dea.Data.GetDataPresent(typeof(Metafile)))
image = (Image)dea.Data.GetData(typeof(Metafile));
else if (dea.Data.GetDataPresent(typeof(Bitmap)))
image = (Image)dea.Data.GetData(typeof(Bitmap));
bIsTarget = true;
Invalidate();
}
}
protected override void OnMouseDown(MouseEventArgs mea) {
if (image != null) {
bIsTarget = false;
DragDropEffects dde = DoDragDrop(image,DragDropEffects.Copy | DragDropEffects.Move);
if (dde == DragDropEffects.Move && !bIsTarget)
image = null;
}
}
}
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