加入FileDB的设计，用于多文件句柄开的过多的问题

Author: ale

CSharp/FileDB.cs

@@ -0,0 +1,206 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using UnityEngine;
+
+namespace ATRI.Collection
+{
+    public class FileDB : IDisposable
+    {
+        #region member
+        // fileOffset, subFileLen, subFile isCopyTo File
+        private Dictionary<string, ValueTuple<int, int, bool, string>> tableInfo = new Dictionary<string, (int, int, bool, string)>();
+        private Dictionary<string, object> tableDict = new Dictionary<string, object>();
+        private FileStream _fs;
+        private string _path;
+        private bool _inited = false;
+        #endregion
+
+        public FileDB(string filePath)
+        {
+            _path = filePath;
+        }
+
+        #region public
+
+        public bool TryGetValueByTableName<TKey, TValue>(string tableName, TKey key, out TValue value) where TKey : IEquatable<TKey>
+        {
+            Init();
+            object dict;
+            if (!tableDict.TryGetValue(tableName, out dict))
+            {
+                ValueTuple<int, int, bool, string> info;
+                if (tableInfo.TryGetValue(tableName, out info))
+                {
+                    // copy value to mergefile
+                    if (!info.Item3)
+                    {
+                        var tempBuff = FileDictionaryUtils.moveTempBuff;
+                        FileStream subFile = new FileStream(info.Item4, FileMode.Open, FileAccess.Read);
+                        int bytesRead;
+                        _fs.Seek(info.Item1, SeekOrigin.Begin);
+                        while ((bytesRead = subFile.Read(tempBuff, 0, tempBuff.Length)) > 0)
+                        {
+                            _fs.Write(tempBuff, 0, bytesRead);
+                        }
+                    }
+                    SubFileStream subFileStream = new SubFileStream(_fs, info.Item1, info.Item2);
+                    dict = new FileDictionary<TKey, TValue>(subFileStream);
+                    tableInfo.Remove(tableName);
+                    tableDict.Add(tableName, dict);
+                }
+                else
+                {
+                    Debug.LogError("tableInfo not init");
+                    value = default(TValue);
+                    return false;
+                }
+            }
+
+            FileDictionary<TKey, TValue> fd = (FileDictionary<TKey, TValue>)dict;
+            return fd.TryGetValue(key, out value);
+        }
+
+        public void Dispose()
+        {
+            if (_fs != null)
+            {
+                _fs.Dispose();
+            }
+        }
+
+        public void MergeRuntime(params string[] paths)
+        {
+            if (File.Exists(_path))
+            {
+                File.Delete(_path);
+            }
+            
+            tableInfo.Clear();
+            _inited = false;
+
+            int len = 0;
+            foreach (var filePath in paths)
+            {
+                FileInfo fi = new FileInfo(filePath);
+                if (!fi.Exists)
+                {
+                    throw new Exception(filePath + " not exit! please check");
+                }
+                string fileName = Path.GetFileNameWithoutExtension(filePath);
+                if (tableInfo.ContainsKey(fileName))
+                {
+                    Debug.LogError(fileName + " already exit!plz check in:[\n"+ string.Concat(paths, "\n") +"]");
+                    return;
+                }
+
+                tableInfo.Add(fileName, (len, (int)fi.Length, false, filePath));
+                len += (int)fi.Length;
+            }
+        }
+
+        #if UNITY_EDITOR
+        public void MergeEditor(params string[] paths)
+        {
+            if (File.Exists(_path))
+            {
+                File.Delete(_path);
+            }
+
+            tableInfo.Clear();
+            _inited = false;
+            
+            FileStream fs = new FileStream(_path, FileMode.CreateNew, FileAccess.Write);
+            BinaryWriter bfw = new BinaryWriter(fs);
+
+            MemoryStream headMs = new MemoryStream();
+            BinaryWriter bw = new BinaryWriter(headMs);
+            
+            int len = 0;
+            bw.Write(paths.Length);
+            Dictionary<string, string> closeSet = new Dictionary<string, string>();
+            foreach (var filePath in paths)
+            {
+                FileInfo fi = new FileInfo(filePath);
+                if (!fi.Exists)
+                {
+                    throw new Exception(filePath + "not eixt! please check");
+                }
+
+                string fileName = Path.GetFileNameWithoutExtension(filePath);
+                if (closeSet.ContainsKey(fileName))
+                {
+                    throw new Exception(filePath + "file name the same with path:" + closeSet[fileName]);
+                }
+
+                byte[] strData = UTF8Encoding.UTF8.GetBytes(fileName);
+                bw.Write(strData.Length);
+                bw.Write(strData);
+                bw.Write(len);
+                bw.Write((int)fi.Length);
+
+                len += (int)fi.Length;
+            }
+
+            int totalHeadLen = (int)headMs.Length;
+            bw.Flush();
+            bw.Close();
+
+            bfw.Write(totalHeadLen);
+            bfw.Write(headMs.ToArray());
+
+            var tempBuff = FileDictionaryUtils.moveTempBuff;
+            
+            foreach (var filePath in paths)
+            {
+                int bytesRead;
+                FileStream subFile = new FileStream(filePath, FileMode.Open, FileAccess.Read);
+                while ((bytesRead = subFile.Read(tempBuff, 0, tempBuff.Length)) > 0)
+                {
+                    fs.Write(tempBuff, 0, bytesRead);
+                }
+            }
+            
+            bfw.Flush();
+            bfw.Close();
+            
+        }
+        #endif
+        
+        #endregion
+
+        private void Init()
+        {
+            if (_inited) return;
+            _inited = true;
+            
+            // merge in runtime
+            if (tableInfo.Count <= 0)
+            {
+                _fs = new FileStream(_path, FileMode.OpenOrCreate, FileAccess.Read);
+                BinaryReader br = new BinaryReader(_fs);
+                int totalHeadLen = br.ReadInt32();
+                int fileLen = br.ReadInt32();
+
+                for (int i = 0; i < fileLen; i++)
+                {
+                    int strLen = br.ReadInt32();
+                    byte[] datas = br.ReadBytes(strLen);
+                    string fileName = UTF8Encoding.UTF8.GetString(datas);
+                    int offset = br.ReadInt32();
+                    int onefileLen = br.ReadInt32();
+
+                    tableInfo.Add(fileName, (offset + totalHeadLen + 4, onefileLen, true, ""));
+                }
+            }
+            else
+            {
+                _fs = new FileStream(_path, FileMode.OpenOrCreate, FileAccess.ReadWrite);
+            }
+        }
+        
+    }
+}