Unity调用windows系统dialog 选择文件夹

#region 调用windows系统dialog 选择文件夹
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]

public class OpenDialogFile
{
public int structSize = 0;
public IntPtr dlgOwner = IntPtr.Zero;
public IntPtr instance = IntPtr.Zero;
public String filter = null;
public String customFilter = null;
public int maxCustFilter = 0;
public int filterIndex = 0;
public String file = null;
public int maxFile = 0;
public String fileTitle = null;
public int maxFileTitle = 0;
public String initialDir = null;
public String title = null;
public int flags = 0;
public short fileOffset = 0;
public short fileExtension = 0;
public String defExt = null;
public IntPtr custData = IntPtr.Zero;
public IntPtr hook = IntPtr.Zero;
public String templateName = null;
public IntPtr reservedPtr = IntPtr.Zero;
public int reservedInt = 0;
public int flagsEx = 0;
}
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public class OpenDialogDir
{
public IntPtr hwndOwner = IntPtr.Zero;
public IntPtr pidlRoot = IntPtr.Zero;
public String pszDisplayName = null;
public String lpszTitle = null;
public UInt32 ulFlags = 0;
public IntPtr lpfn = IntPtr.Zero;
public IntPtr lParam = IntPtr.Zero;
public int iImage = 0;
}

public class DllOpenFileDialog
{
[DllImport("Comdlg32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]
public static extern bool GetOpenFileName([In, Out] OpenDialogFile ofn);

[DllImport("Comdlg32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]
public static extern bool GetSaveFileName([In, Out] OpenDialogFile ofn);

[DllImport("shell32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]
public static extern IntPtr SHBrowseForFolder([In, Out] OpenDialogDir ofn);

[DllImport("shell32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]
public static extern bool SHGetPathFromIDList([In] IntPtr pidl, [In, Out] char[] fileName);

}

public string OpenWindowsDialog()
{
OpenDialogDir ofn2 = new OpenDialogDir();
ofn2.pszDisplayName = new string(new char[2000]); ; // 存放目录路径缓冲区
ofn2.lpszTitle = "Open Project";// 标题
//ofn2.ulFlags = BIF_NEWDIALOGSTYLE | BIF_EDITBOX; // 新的样式,带编辑框
IntPtr pidlPtr = DllOpenFileDialog.SHBrowseForFolder(ofn2);

char[] charArray = new char[2000];
for (int i = 0; i < 2000; i++)
charArray[i] = '\0';

DllOpenFileDialog.SHGetPathFromIDList(pidlPtr, charArray);
string fullDirPath = new String(charArray);

fullDirPath = fullDirPath.Substring(0, fullDirPath.IndexOf('\0'));

return fullDirPath;//这个就是选择的目录路径。
}
#endregion