/// <summary>
/// Gets file icon as <b>Bitmap</b>.
/// Returns null if the icon is not cached and failed to get it, eg file does not exist.
/// </summary>
/// <param name="file">Any file or folder.</param>
/// <param name="useExt">
/// Get file type icon, depending on filename extension. Use this to avoid getting separate image object for each file of same type.
/// This is ignored if filename extension is ".ico" or ".exe" or starts with ".exe," or ".dll,".
/// </param>
/// <param name="giFlags">Flags for <see cref="AIcon.GetFileIconImage"/>.</param>
/// <param name="autoUpdate">
/// If not null, the cached image will be auto-updated when changed. Then will be called this function. It can update the image in UI.
/// How it works: If this function finds cached image, it sets timer that after ~50 ms loads that icon/image from file again and compares with the cached image. If different, updates the cache. Does it once, not periodically.
/// Use only in UI threads. Does not work if this thread does not retrieve/dispatch posted messages.
/// </param>
/// <param name="auParam">Something to pass to the <i>autoUpdate</i> callback function.</param>
/// <remarks>
/// If the icon is in the memory cache, gets it from there.
/// Else if it is in the file cache, gets it from there and adds to the memory cache.
/// Else gets from file (uses <see cref="AIcon.GetFileIconImage"/> and adds to the file cache and to the memory cache.
/// </remarks>
public Bitmap GetImage(string file, bool useExt, IconGetFlags giFlags = 0, Action <Bitmap, object> autoUpdate = null, object auParam = null)
{
if (useExt)
{
var ext = APath.GetExtension(file);
if (ext.Length == 0)
{
if (AFile.ExistsAsDirectory(file))
{
ext = file;
}
else
{
ext = ".no-ext";
}
}
else
{
//ext = ext.Lower();
if (ext.Eqi(".ico") || ext.Eqi(".exe") || ext.Starts(".exe,", true) || ext.Starts(".dll,", true))
{
ext = file;
}
}
file = ext;
}
else if (APath.IsFullPathExpandEnvVar(ref file))
{
file = APath.Normalize_(file, noExpandEV: true);
}
return(_GetImage(file, giFlags, null, autoUpdate, auParam, true));
}
/// <summary>
/// Gets file path extension like ".txt" or URL protocol like "http".
/// Returns null if path does not end with ".extension" and does not start with "protocol:"; also if starts with "shell:".
/// </summary>
/// <param name="path">File path or URL. Can be just extension like ".txt" or protocol like "http:".</param>
/// <param name="isProtocol">Receives true if URL or protocol.</param>
internal static string GetExtensionOrProtocol(string path, out bool isProtocol)
{
isProtocol = false;
if (path.NE())
{
return(null);
}
if (!PathIsExtension(path))
{
int i = path.IndexOf(':');
if (i > 1)
{
path = path.Remove(i); //protocol
if (path == "shell")
{
return(null); //eg "shell:AppsFolder\Microsoft.WindowsCalculator_8wekyb3d8bbwe!App"
}
isProtocol = true;
}
else
{
path = APath.GetExtension(path);
if (path.NE())
{
return(null);
}
}
}
return(path);
}