/// <summary>
/// Returns the data packed after the DROPFILES structure.
/// </summary>
/// <param name="dropHandle"></param>
/// <returns></returns>
internal static string GetData(IntPtr dropHandle)
{
IntPtr data = UnsafeNativeMethods.GlobalLock(dropHandle);
try {
_DROPFILES df = (_DROPFILES)Marshal.PtrToStructure(data, typeof(_DROPFILES));
if (df.fWide != 0)
{
IntPtr pdata = new IntPtr((long)data + df.pFiles);
return(Marshal.PtrToStringUni(pdata));
}
} finally {
if (data != IntPtr.Zero)
{
UnsafeNativeMethods.GlobalUnLock(data);
}
}
return(null);
}
private IntPtr PackageSelectionData(StringBuilder sb, bool addEndFormatDelimiter) {
if (sb == null || sb.ToString().Length == 0 || this.ItemsDraggedOrCutOrCopied.Count == 0) {
return IntPtr.Zero;
}
// Double null at end.
if (addEndFormatDelimiter) {
if (sb.ToString()[sb.Length - 1] != '\0') {
sb.Append('\0');
}
}
// We request unmanaged permission to execute the below.
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Demand();
_DROPFILES df = new _DROPFILES();
int dwSize = Marshal.SizeOf(df);
Int16 wideChar = 0;
int dwChar = Marshal.SizeOf(wideChar);
int structSize = dwSize + ((sb.Length + 1) * dwChar);
IntPtr ptr = Marshal.AllocHGlobal(structSize);
df.pFiles = dwSize;
df.fWide = 1;
IntPtr data = IntPtr.Zero;
try {
data = UnsafeNativeMethods.GlobalLock(ptr);
Marshal.StructureToPtr(df, data, false);
IntPtr strData = new IntPtr((long)data + dwSize);
DragDropHelper.CopyStringToHGlobal(sb.ToString(), strData, structSize);
} finally {
if (data != IntPtr.Zero)
UnsafeNativeMethods.GlobalUnLock(data);
}
return ptr;
}