unity3d，C#使用sqlite作为数据库解决方案思路

1，编辑器建立好数据库结构，生成sqlite数据库文件，可以用navicat图形界面编辑器来操作。
2，建立好的数据库，后缀名变为.txt格式（方便unity3d加载），放文件放到Assest/Resources目录下（新建目录）。
放在Resources目录下的文件，在Pc/ios/android端均可以不作区分的用Resource来加载，假设数据库文件名位：data.txt,语句如下：
TextAsset txt = Resources.Load ("data", typeof(TextAsset))as TextAsset;
3, 将读取到的TextAsset文件写入对应平台的沙盒路径下, 代码为：
   databaseFilePath = Application.persistentDataPath+"//"+data.db;（沙盒，各平台路径不同，均为可读写）
      File.WriteAllBytes(databaseFilePath,txt.bytes);
4，加载沙盒路径下的数据库文件进行读写操作。DbAccess封装了数据库操作。其中需要两个dll文件，一个so文件（android平台需要libsq

using UnityEngine;

using System.Collections;
using Mono.Data.Sqlite;
using System;
using System.IO;

public class DbAccess{

	private SqliteConnection dbConnection;
	
	private SqliteCommand dbCommand;
	
	private SqliteDataReader reader;
	
	public DbAccess (string connectionString)
	{
		OpenDB (connectionString);
	}
	public DbAccess ()
	{
		
	}

	public void OpenDB (string connectionString)
	{
		try
		{
			dbConnection = new SqliteConnection (connectionString);
			
			dbConnection.Open ();
			
			Debug.Log ("Connected to db");
		}
		catch(Exception e)
		{
			string temp1 = e.ToString();
			Debug.Log(temp1);
		}
	}
	
	public void CloseSqlConnection ()
	{
		
		if (dbCommand != null) {
			
			dbCommand.Dispose ();
			
		}
		
		dbCommand = null;
		
		if (reader != null) {
			
			reader.Dispose ();
			
		}
		
		reader = null;
		
		if (dbConnection != null) {
			
			dbConnection.Close ();
			
		}
		
		dbConnection = null;
		
		Debug.Log ("Disconnected from db.");
		
	}
	
	public SqliteDataReader ExecuteQuery (string sqlQuery)
		
	{
		
		dbCommand = dbConnection.CreateCommand ();
		
		dbCommand.CommandText = sqlQuery;
		
		reader = dbCommand.ExecuteReader ();
		
		return reader;
		
	}
	
	public SqliteDataReader ReadFullTable (string tableName)
		
	{
		
		string query = "SELECT * FROM " + tableName;
		
		return ExecuteQuery (query);
		
	}
	
	public SqliteDataReader InsertInto (string tableName, string[] values)
		
	{
		
		string query = "INSERT INTO " + tableName + " VALUES (" + values[0];
		
		for (int i = 1; i < values.Length; ++i) {
			
			query += ", " + values[i];
			
		}
		
		query += ")";
		
		return ExecuteQuery (query);
		
	}
	
	public SqliteDataReader UpdateInto (string tableName, string []cols,string []colsvalues,string selectkey,string selectvalue)
	{
		
		string query = "UPDATE "+tableName+" SET "+cols[0]+" = "+colsvalues[0];
		
		for (int i = 1; i < colsvalues.Length; ++i) {
			
			query += ", " +cols[i]+" ="+ colsvalues[i];
		}
		
		query += " WHERE "+selectkey+" = "+selectvalue+" ";
		
		return ExecuteQuery (query);
	}
	
	public SqliteDataReader Delete(string tableName,string []cols,string []colsvalues)
	{
		string query = "DELETE FROM "+tableName + " WHERE " +cols[0] +" = " + colsvalues[0];
		
		for (int i = 1; i < colsvalues.Length; ++i) {
			
			query += " or " +cols[i]+" = "+ colsvalues[i];
		}
		Debug.Log(query);
		return ExecuteQuery (query);
	}
	
	public SqliteDataReader InsertIntoSpecific (string tableName, string[] cols, string[] values)
		
	{
		
		if (cols.Length != values.Length) {
			
			throw new SqliteException ("columns.Length != values.Length");
			
		}
		
		string query = "INSERT INTO " + tableName + "(" + cols[0];
		
		for (int i = 1; i < cols.Length; ++i) {
			
			query += ", " + cols[i];
			
		}
		
		query += ") VALUES (" + values[0];
		
		for (int i = 1; i < values.Length; ++i) {
			
			query += ", " + values[i];
			
		}
		
		query += ")";
		
		return ExecuteQuery (query);
		
	}
	
	public SqliteDataReader DeleteContents (string tableName)
		
	{
		
		string query = "DELETE FROM " + tableName;
		
		return ExecuteQuery (query);
		
	}
	
	public SqliteDataReader CreateTable (string name, string[] col, string[] colType)
		
	{
		
		if (col.Length != colType.Length) {
			
			throw new SqliteException ("columns.Length != colType.Length");
			
		}
		
		string query = "CREATE TABLE " + name + " (" + col[0] + " " + colType[0];
		
		for (int i = 1; i < col.Length; ++i)
		{
			
			query += ", " + col[i] + " " + colType[i];
			
		}
		
		query += ")";
		
		return ExecuteQuery (query);
		
	}
	
	public SqliteDataReader SelectWhere (string tableName, string[] items, string[] col, string[] operation, string[] values)
		
	{
		
		if (col.Length != operation.Length ||operation.Length != values.Length) {
			
			throw new SqliteException ("col.Length != operation.Length != values.Length");
			
		}
		
		string query = "SELECT " + items[0];
		
		for (int i = 1;i < items.Length; ++i) {
			
			query += ", " + items[i];
			
		}
		if (col.Length == 0) {
			query += " FROM " + tableName;
		} else 
		{
			query += " FROM " + tableName + " WHERE " + col[0] + operation[0] + "'" + values[0] + "' ";

			for (int i = 1; i < col.Length; ++i) {
				
				query += " AND " + col[i] + operation[i] + "'" + values[0] + "' ";
				
			}
		}
	
		return ExecuteQuery (query);
		
	}
}

public class DataCenter{

	private string databaseFilename = "data.db";

	private string databaseFilePath;

	private DbAccess dbaccess;

	public DataCenter()
	{
		databaseFilePath = Application.persistentDataPath+"//"+databaseFilename;

		if (!File.Exists (databaseFilePath)) 
		{
			TextAsset txt = Resources.Load ("data", typeof(TextAsset))as TextAsset;

			File.WriteAllBytes(databaseFilePath,txt.bytes);

			//copy data file to sandbox
		}
		
		dbaccess = new DbAccess (@"Data Source=" + databaseFilePath);
	}
}