C# 在xmpdc:Subject字段中存储数组

我试图复制Adobe Lightroom如何在图像（JPEG）结构中存储“关键字”

到目前为止，我发现关键字存储在字段中的元数据中

/xmp/dc：主题

Light room将每个标记存储为xml结构，格式如下：

<dc:subject>
    <rdf:Bag>
        <rdf:li>Bianca</rdf:li>
        <rdf:li>KEYWORDS -LR</rdf:li>
        <rdf:li>Laura</rdf:li>
        <rdf:li>Lyndel</rdf:li>
        <rdf:li>T-ALL</rdf:li>
    </rdf:Bag>
</dc:subject>

<dc:subject>Bianca; KEYWORDS -LR; Laura; Lyndel; T-ALL</dc:subject>

编辑：

在该链接中，显示了应在以下查询中进行写入：

/xmp/dc:subject

但是它是什么呢

Edit2:

结果表明，写入“位置”如下所示：

/xmp/dc:subject/{ulong=0}

/xmp/dc:subject/{ulong=1}

//读取图像流
使用（var originalFile=File.Open（路径，FileMode.Open，FileAccess.Read，FileShare.None））
{
//创建位图解码器
decoder=BitmapDecoder.Create（原始文件、createOptions、BitmapCacheOption.None）；
//第一帧包含图像元数据
var bitmapFrame=decoder.Frames[0]；
if（bitmapFrame！=null&&bitmapFrame.Metadata！=null）
{
//为了能够修改元数据，首先我们需要克隆它
BitmapMetadata metadata=bitmapFrame.metadata.Clone（）作为BitmapMetadata；
//删除XP主题字段
metadata.RemoveQuery（“System.Subject”）；
//删除XP关键字字段
metadata.RemoveQuery（“System.Keywords”）；
//写标签（照明室钥匙用语）
var关键字=“K1；K2；K3”；
var keywordArray=keywords.Split（新[]{；“}，StringSplitOptions.RemoveEmptyEntries）；
//写入XMP部分
SetQuery（“/xmp/dc:Subject”，新的位图元数据（“xmpbag”）；
for（var i=0；i

// Read the image stream
using (var originalFile = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.None))
{
    // Create the bitmap decoder
    decoder = BitmapDecoder.Create(originalFile, createOptions, BitmapCacheOption.None);

    // The the first frame contains the image metadata
    var bitmapFrame = decoder.Frames[0];

    if (bitmapFrame != null && bitmapFrame.Metadata != null)
    {
        // To be able to modify the metadata, first we need to clone it
        BitmapMetadata metadata = bitmapFrame.Metadata.Clone() as BitmapMetadata;

        // Remove the XP Subject field
        metadata.RemoveQuery("System.Subject");

        // Remove the XP keyword field
        metadata.RemoveQuery("System.Keywords");
        
        // Write Tags (Lightroom keywording)
        string keywords = "K1; K2; K3";
        metadata.SetQuery("/xmp/dc:Subject", keywords);
        
        // Create a bitmap encoder
        var encoder = CreateBitmapEncoder(imageFormat);

        // Create new frame with the updated metadata
        // Keep everything the same except the updated metadata
        encoder.Frames.Add(BitmapFrame.Create(
            bitmapFrame, bitmapFrame.Thumbnail, metadata, bitmapFrame.ColorContexts));

        // Attemp to save the update image
        using (Stream outputFile = File.Open(path + tempSufix, FileMode.Create, FileAccess.ReadWrite))
        {
            encoder.Save(outputFile);
        }
    }
}

// Read the image stream
using (var originalFile = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.None))
{
    // Create the bitmap decoder
    decoder = BitmapDecoder.Create(originalFile, createOptions, BitmapCacheOption.None);

    // The the first frame contains the image metadata
    var bitmapFrame = decoder.Frames[0];

    if (bitmapFrame != null && bitmapFrame.Metadata != null)
    {
        // To be able to modify the metadata, first we need to clone it
        BitmapMetadata metadata = bitmapFrame.Metadata.Clone() as BitmapMetadata;

        // Remove the XP Subject field
        metadata.RemoveQuery("System.Subject");

        // Remove the XP keyword field
        metadata.RemoveQuery("System.Keywords");

        // Write Tags (Lightroom keywording)
        var keywords = "K1; K2; K3";
        var keywordArray = keywords.Split(new[] { "; " }, StringSplitOptions.RemoveEmptyEntries);

        // Write in the XMP section
        metadata.SetQuery("/xmp/dc:Subject", new BitmapMetadata("xmpbag"));
        for (var i = 0; i < keywordArray.Length; i++)
        {
            var order = "/{ulong=" + i + "}";
            var keyword = keywordArray[i];
            metadata.SetQuery("/xmp/<xmpbag>dc:Subject" + order, keyword);
        }

        // Write in the IPTC section
        metadata.SetQuery("/app13/irb/8bimiptc/iptc/{str=Keywords}", keywordArray);

        // Create a bitmap encoder
        var encoder = CreateBitmapEncoder(imageFormat);

        // Create new frame with the updated metadata
        // Keep everything the same except the updated metadata
        encoder.Frames.Add(BitmapFrame.Create(
            bitmapFrame, bitmapFrame.Thumbnail, metadata, bitmapFrame.ColorContexts));

        // Attemp to save the update image
        using (Stream outputFile = File.Open(path + tempSufix, FileMode.Create, FileAccess.ReadWrite))
        {
            encoder.Save(outputFile);
        }
    }
}