c# - 如何将对象保存到 Visual Studio 中的 fooSettings.settings 文件？

Question

您可以将对象保存到 Visual Studio 中的 settings.settings 文件吗？如果是这样怎么办？我认为您可以使您的对象可序列化并且它应该持续存在，但我不确定我是否做对了，即当我尝试取回该对象时它始终为空。

代码如下:

    [Serializable()]
    [XmlRoot(ElementName = "LayerTCA", IsNullable = false, Namespace = "http://somesite.com")]
    public class LayerTCA
    {
        //This is a COM object so I don't want to serialize this.
        IFeatureClass featureClass;

        string fullName;
        string basicName;

        public LayerTCA()
        {

        }

        public LayerTCA(IFeatureClass featureClass)
        {
            FeatureClass = featureClass;
        }


        public IFeatureClass FeatureClass
        {
            get { return featureClass; }
            set 
            {
                featureClass = value;
                fullName = featureClass.AliasName;
                basicName = StringHelper.StringAfterLastFullStop(fullName);
            }
        }

        [XmlAttribute(AttributeName = "BasicName")]  
        public string BasicName
        {
            get { return basicName; }
            set { basicName = value; }
        }


        [XmlAttribute(AttributeName = "FullName")]  
        public string FullName
        {
            get { return fullName; }
            set { fullName = value; }
        }

        public override string ToString()
        {
            return FullName;
        }

    }

Answer 1

我会使用一个 IFeatureClassName 成员变量。构造函数将接受 IFeature 类，然后将要素类转换为 IDataset，并将成员变量设置为 IDataset.FullName。这将是一个 IName。所有 IName 对象都可以通过 IPersistStream 持久化。虽然不能直接序列化为 xml，但可以将 IPersistStream 对象写入 byte[](通过 MemoryBlobStream)。不记得 byte[] 是否可以通过 XmlAttribute 公开，可能应该使用 base64。可能还有一个 Open 方法将简单地调用 IName.Open 在包含的成员 featureclassname 变量上，返回一个 IFeatureclass。

更新:这里有一些代码可能有助于将要素类名称与字符串相互转换。

public static void TestIt(IFeatureClass fc)
{
    string guidplusbase64Name = GetFullName((IDataset)fc);
    Debug.Print(guidplusbase64Name);
    IFeatureClass fc2 = OpenDataset(guidplusbase64Name) as IFeatureClass;
    Debug.Print(fc2.AliasName);            
}

public static string GetFullName(IDataset ds)
{
    IPersistStream ps = ds.FullName as IPersistStream;
    Guid g;
    ps.GetClassID(out g);            
    IMemoryBlobStream mbs = new MemoryBlobStreamClass();
    ps.Save(mbs,0);
    object bytes;
    ((IMemoryBlobStreamVariant)mbs).ExportToVariant(out bytes);            
    return String.Format("{0};{1}",g,Convert.ToBase64String((byte[])bytes));
}

public static IDataset OpenDataset(string guidplusbase64Name)
{
    int idx = guidplusbase64Name.IndexOf(";");
    string base64Name = guidplusbase64Name.Substring(idx+1);
    string guidString = guidplusbase64Name.Substring(0, idx);

    byte[] bytes = Convert.FromBase64String(base64Name);
    IMemoryBlobStream mbs = new MemoryBlobStreamClass();
    ((IMemoryBlobStreamVariant)mbs).ImportFromVariant(bytes);
    Type t = Type.GetTypeFromCLSID(new Guid(guidString));
    IName n = Activator.CreateInstance(t) as IName;
    ((IPersistStream)n).Load(mbs);
    IDataset ds = n.Open() as IDataset;
    return ds;
}

(已更新以适用于任何 IDataset，而不仅仅是要素类)(更新 2:连接 clsid 允许它与任何数据集一起工作，以前的版本是硬连线的 featureclassname)

别问我为什么 ESRI 还没有抽出时间实现 IName.NameString .

The NameString property is reserved for future use. When implemented, it will return a string representation of the locational component of the name object that may be persisted by applications.