java - 在带有 JNA 的 Java 中使用 SHGetFileInfo

Question

我尝试使用 JNA 将 SHGetFileInfo 函数从 Shell32 翻译成 Java，并使用了 C# 代码和 this作为引用

虽然在 C# 代码中 psfi.iIcon 是 432，但在我翻译的 Java 代码中 psfi.iIcon 是 0。如果我是对的，对于同一个文件，无论我使用哪种语言，它们都应该相同，不是吗？

我的 Java 代码:

public static void main(String[] args) {
    String path = "[PATH_TO_EXE]\\test.exe"; //Of course in my code I used the real path

    SHFILEINFO sfi = new SHFILEINFO();
    DWORD_PTR i = Shell32.INSTANCE.SHGetFileInfo(path, 0, sfi, sfi.size(), SHGFI.SysIconIndex);

    System.out.println(sfi.iIcon); //<-- Prints 0, should print 432
}

public static class SHGFI {
    static final int SysIconIndex = 0x000004000;
    static final int LargeIcon = 0x000000000;
    static final int UseFileAttributes = 0x000000010;
}

public interface Shell32 extends StdCallLibrary {
    Shell32 INSTANCE = Native.loadLibrary("shell32", Shell32.class, W32APIOptions.UNICODE_OPTIONS);
    DWORD_PTR SHGetFileInfo(String pszPath, int dwFileAttributes, SHFILEINFO psfi, int cbFileInfo, int uFlags);
}

public static class SHFILEINFO extends Structure {
    public HICON hIcon;
    public int iIcon;
    public DWORD dwAttributes;
    public char[] szDisplayName = new char[260];
    public char[] szTypeName = new char[80];

    @Override
    protected List<String> getFieldOrder() {
        return Arrays.asList("hIcon", "iIcon", "dwAttributes", "szDisplayName", "szTypeName");
    }
}

我有没有做错什么基本的事情？我是 JNA 和 Windows 函数的新手

Answer 1

在备注 部分下，有这条信息，恕我直言，这可能是您问题的根源

You must initialize Component Object Model (COM) with CoInitialize or OleInitialize prior to calling SHGetFileInfo.

这是一个非常简单的调用

CoInitialize(null);

---

正如 DanielWiddis 在评论中指出的那样，根据文档

New applications should call CoInitializeEx instead of CoInitialize

和

To close the COM library gracefully, each successful call to CoInitialize or CoInitializeEx, including those that return S_FALSE, must be balanced by a corresponding call to CoUninitialize

例子

CoInitializeEx(null, 0);
CoUninitialize();