C# (Craft.Net.Client) ServerList异常

Question

我正在使用Craft.Net.Client库，但是在尝试使用ServerList.SaveTo(字符串文件)方法时出错了:无法在流结束后读取(EndOfStreamException)

ServerList.cs：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using fNbt;

namespace Craft.Net.Client
{
/// <summary>
/// Provides functionality for interacting with
/// the saved vanilla server list.
/// </summary>
public class ServerList
{
    public static string ServersDat
    {
        get
        {
            return Path.Combine(DotMinecraft.GetDotMinecraftPath(), "servers.dat");
        }
    }

    public ServerList()
    {
        Servers = new List<Server>();
    }

    public List<Server> Servers { get; set; }

    public void Save()
    {
        SaveTo(ServersDat);
    }

    public void SaveTo(string file)
    {
        var nbt = new NbtFile(file); // ERROR : Unable to read beyond the end of the  stream (EndOfStreamException)
        nbt.RootTag = new NbtCompound("");
        var list = new NbtList("servers", NbtTagType.Compound);
        foreach (var server in Servers)
        {
            var compound = new NbtCompound();
            compound.Add(new NbtString("name", server.Name));
            compound.Add(new NbtString("ip", server.Ip));
            compound.Add(new NbtByte("hideAddress", (byte)(server.HideAddress ? 1 : 0)));
            compound.Add(new NbtByte("acceptTextures", (byte)(server.AcceptTextures ? 1 : 0)));
            list.Add(compound);
        }
        nbt.RootTag.Add(list);
        nbt.SaveToFile(file, NbtCompression.None);
    }

    public static ServerList Load()
    {
        return LoadFrom(ServersDat);
    }

    public static ServerList LoadFrom(string file)
    {
        var list = new ServerList();
        var nbt = new NbtFile(file);
        foreach (NbtCompound server in nbt.RootTag["servers"] as NbtList)
        {
            var entry = new Server();
            if (server.Contains("name"))
                entry.Name = server["name"].StringValue;
            if (server.Contains("ip"))
                entry.Ip = server["ip"].StringValue;
            if (server.Contains("hideAddress"))
                entry.HideAddress = server["hideAddress"].ByteValue == 1;
            if (server.Contains("acceptTextures"))
                entry.AcceptTextures = server["acceptTextures"].ByteValue == 1;
            list.Servers.Add(entry);
        }
        return list;
    }

    public class Server
    {
        public string Name { get; set; }
        public string Ip { get; set; }
        public bool HideAddress { get; set; }
        public bool AcceptTextures { get; set; }

        public override string ToString()
        {
            return Name;
        }
    }
}

}

我称之为方法的地方：

ServerList.Server server = new ServerList.Server();
server.Name = "x";
server.Ip = "x";
server.HideAddress = true;
server.AcceptTextures = true;

ServerList list = new ServerList();
list.Servers.Add(server);
if (!File.Exists(RuntimeInfo.getMinecraftDir() + @"\servers.dat"))
{
File.Create(RuntimeInfo.getMinecraftDir() + @"\servers.dat");
}
list.SaveTo(RuntimeInfo.getMinecraftDir() + @"\servers.dat");

我注意到的一件事是，只有当servers.dat为空时才会收到错误，而如果已经保存了服务器，则不会得到错误。

有谁可以帮我？

提前谢谢你，

编辑:多亏了steveg89，下面的解决方案解决了问题(更新SaveTo方法)：

    public void SaveTo(string file)
    {
    NbtFile nbt;
    if (File.Exists(RuntimeInfo.getMinecraftDir() + @"\servers.dat"))
    {
        nbt = new NbtFile();
        nbt.SaveToFile(RuntimeInfo.getMinecraftDir() + @"\servers.dat", NbtCompression.None);
    }
    else
        nbt = new NbtFile();

    nbt.RootTag = new NbtCompound("");
    var list = new NbtList("servers", NbtTagType.Compound);
    foreach (var server in Servers)
    {
        var compound = new NbtCompound();
        compound.Add(new NbtString("name", server.Name));
        compound.Add(new NbtString("ip", server.Ip));
        compound.Add(new NbtByte("hideAddress", (byte)(server.HideAddress ? 1 : 0)));
        compound.Add(new NbtByte("acceptTextures", (byte)(server.AcceptTextures ? 1 : 0)));
        list.Add(compound);
    }
    nbt.RootTag.Add(list);
    nbt.SaveToFile(file, NbtCompression.None);           
}

Answer 1

我注意到他们的NbtFile构造函数试图从文件中读取。它假设文件的格式已经正确。这意味着你必须创建并保存它。他们的API应该为您处理这个问题，但是没有，所以试试下面这个

if (!File.Exists(RuntimeInfo.getMinecraftDir() + @"\servers.dat"))
{
   NbtFile nbt = new NbtFile();
   nbt.SaveToFile(RuntimeInfo.getMinecraftDir() + @"\servers.dat", Nbt.Compression.None);
}

我认为更明智的方法是纠正SaveTo的ServerList方法。这种方法意味着您不必在代码中检查它，但它确实意味着您将使用您自己的Craft.Net风格。我会这样做：

public void SaveTo(string file)
        {
            NbtFile nbt;
            if( File.Exists( file ) )
            {
              nbt = new NbtFile(file);
            }
            else
            {
              nbt = new NbtFile();
            }
            nbt.RootTag = new NbtCompound("");
            var list = new NbtList("servers", NbtTagType.Compound);
            foreach (var server in Servers)
            {
                var compound = new NbtCompound();
                compound.Add(new NbtString("name", server.Name));
                compound.Add(new NbtString("ip", server.Ip));
                compound.Add(new NbtByte("hideAddress", (byte)(server.HideAddress ? 1 : 0)));
                compound.Add(new NbtByte("acceptTextures", (byte)(server.AcceptTextures ? 1 : 0)));
                list.Add(compound);
            }
            nbt.RootTag.Add(list);
            nbt.SaveToFile(file, NbtCompression.None);
        }