private void Load(Stream str)
{
//read the file header and check
ICONDIR fileheader = new ICONDIR(str);
if (fileheader.idType != 1)
{
throw new Exception("this is not an icon file");
}
if (fileheader.idCount < 1)
{
throw new Exception("no iconimages contained");
}
//read direntries
ICONDIRENTRY[] entries = new ICONDIRENTRY[fileheader.idCount];
for (int i = 0; i < fileheader.idCount; i++)
{
entries[i] = new ICONDIRENTRY(str);
}
//read images
for (int i = 0; i < fileheader.idCount; i++)
{
_images.Add(IconImage.FromStream(str));
}
}
/// <summary>
/// saves the icon to a stream
/// </summary>
public unsafe void Save(Stream str)
{
if (str == null)
{
throw new ArgumentNullException("str");
}
if (_images.Count < 1)
{
throw new Exception("icon is empty");
}
//write file header
ICONDIR fileheader = new ICONDIR((short)(_images.Count));
fileheader.Write(str);
//write direntries
int fileoffset = sizeof(ICONDIR) +
_images.Count * sizeof(ICONDIRENTRY);
foreach (IconImage img in _images)
{
ICONDIRENTRY entry = img.GetEntry();
entry.FileOffset = fileoffset;
fileoffset += entry.SizeInBytes;
entry.Write(str);
}
//write images
foreach (IconImage img in _images)
{
img.Write(str);
}
}
/// <summary>
/// constructs an icon from a dll resource
/// </summary>
private static Icon IconFromLibrary(IntPtr hlibrary, object resourceid)
{
IntPtr hicon;
//is_intresource
if (resourceid is int)
{
hicon = Kernel32.FindResource(hlibrary, (int)resourceid, Kernel32.RT_GROUP_ICON);
}
else if (resourceid is string)
{
hicon = Kernel32.FindResource(hlibrary, (string)resourceid, Kernel32.RT_GROUP_ICON);
}
else
{
throw new ArgumentException("resourceid is invalid type", "resourceid");
}
//open stream
MEMICONDIRENTRY[] entries;
using (Stream str = Kernel32.GetStreamFromResource(hlibrary, hicon))
{
ICONDIR header = new ICONDIR(str);
if (header.idType != 1)
{
throw new Exception("this is not an icon file");
}
if (header.idCount < 1)
{
throw new Exception("no iconimages contained");
}
//read headers
entries = new MEMICONDIRENTRY[header.idCount];
for (int i = 0; i < entries.Length; i++)
{
entries[i] = new MEMICONDIRENTRY(str);
}
}
Icon ret = new Icon();
//read images
for (int i = 0; i < entries.Length; i++)
{
//stream for single image
using (Stream str = Kernel32.GetStreamFromResource(hlibrary,
Kernel32.FindResource(hlibrary, entries[i].ID, Kernel32.RT_ICON)))
{
ret.Images.Add(IconImage.FromStream(str));
}
}
return(ret);
}