private static List <IcImage> GetImages(Icon ico)
{
List <IcImage> l = new List <IcImage>();
byte[] pb;
using (MemoryStream ms = new MemoryStream())
{
ico.Save(ms);
pb = ms.ToArray();
}
const int cbDir = NativeMethods.ICONDIRSize;
if (Marshal.SizeOf(typeof(ICONDIR)) != cbDir)
{
Debug.Assert(false); return(l);
}
const int cbEntry = NativeMethods.ICONDIRENTRYSize;
if (Marshal.SizeOf(typeof(ICONDIRENTRY)) != cbEntry)
{
Debug.Assert(false); return(l);
}
int iPos = 0;
ICONDIR d = MemUtil.BytesToStruct <ICONDIR>(pb, iPos);
iPos += cbDir;
if (d.idReserved != 0)
{
Debug.Assert(false); return(l);
}
if (d.idType != 1)
{
Debug.Assert(false); return(l);
}
for (uint u = 0; u < d.idCount; ++u)
{
IcImage img = new IcImage();
img.Entry = MemUtil.BytesToStruct <ICONDIRENTRY>(pb, iPos);
iPos += cbEntry;
img.Data = MemUtil.Mid(pb, (int)img.Entry.dwImageOffset,
(int)img.Entry.dwBytesInRes);
l.Add(img);
}
#if DEBUG
int cbSum = cbDir + (l.Count * cbEntry);
foreach (IcImage img in l)
{
cbSum += img.Data.Length;
}
Debug.Assert(cbSum == pb.Length); // No extra data
#endif
return(l);
}
private static Icon CreateIcon(List <IcImage> l)
{
int n = l.Count;
if ((n <= 0) || (n > ushort.MaxValue))
{
Debug.Assert(false); return(null);
}
const int cbDir = NativeMethods.ICONDIRSize;
if (Marshal.SizeOf(typeof(ICONDIR)) != cbDir)
{
Debug.Assert(false); return(null);
}
const int cbEntry = NativeMethods.ICONDIRENTRYSize;
if (Marshal.SizeOf(typeof(ICONDIRENTRY)) != cbEntry)
{
Debug.Assert(false); return(null);
}
int iData = cbDir + (n * cbEntry);
for (int i = 0; i < n; ++i)
{
int cb = l[i].Data.Length;
Debug.Assert(l[i].Entry.dwBytesInRes == cb);
l[i].Entry.dwBytesInRes = (uint)cb;
l[i].Entry.dwImageOffset = (uint)iData;
iData += cb;
}
byte[] pbIco;
using (MemoryStream ms = new MemoryStream(iData))
{
ICONDIR d = new ICONDIR();
d.idType = 1;
d.idCount = (ushort)n;
byte[] pb = MemUtil.StructToBytes <ICONDIR>(ref d);
Debug.Assert(pb.Length == cbDir);
MemUtil.Write(ms, pb);
for (int i = 0; i < n; ++i)
{
ICONDIRENTRY e = l[i].Entry;
pb = MemUtil.StructToBytes <ICONDIRENTRY>(ref e);
Debug.Assert(pb.Length == cbEntry);
MemUtil.Write(ms, pb);
}
for (int i = 0; i < n; ++i)
{
MemUtil.Write(ms, l[i].Data);
}
pbIco = ms.ToArray();
}
Debug.Assert(pbIco.Length == iData);
Icon ico;
using (MemoryStream msRead = new MemoryStream(pbIco, false))
{
ico = new Icon(msRead);
}
return(ico);
}
