unity编辑器xml数据库插件

unity编辑器xml数据库插件

注：9月9日更新，其中MyXML.cs中有一句代码写错，查找功能失误，文中已经修改！

注：9月1日更新说明：xml存储结构，因为在用xml之前不知道正规的xml数据结构，所以是自创的结构。虽然也能完成功能，但是据说策划配置时不方便，所以为了统一，不使用节点的方式存储数据，

而是通过添加属性，设置属性的方式来存取数据。

直接上图看的清楚些：

我之前设计的格式：

现在的格式：

关于这部分的代码我会贴在最后。

程序和数据分离的意义我就不多说了，大家自己脑补或者百度。在使用unity开发时，数据的调试是非常频繁和重要的。我们可以制作一个简单的编辑器插件，将数据显示在Inspector面板上，并进行编辑操作。这样测试人员就可以非常方便的管理测试数据了。

需求很简单，具体的效果是，能读取资源内的类，将其属性显示在面板上，可以对此进行增删改查的操作。如下图所示（对象组，相当于数据库所有的表。对象，相当于表的所有记录）。

 

 

当需要创建一条新记录的时候，先填上主键，然后点击创建按钮。编辑完成后点击插入即可。

 

 

xml数据库文件如下图

要实现这个功能，需要的知识是，C#的反射类，unity的编辑器类，数据库。通过反射，自动解析对象，获取对象的成员变量名和值。Unity编辑器类没什么好说的，就是一些组件方法的使用。考虑到跨平台等问题，我选择xml作为存储数据库。编辑器内运行，存储量不大，所以性能方面的问题也就不说了。

好，接下来说一说设计的事。首先是对象的反射。基本类型的存储没有问题，难点是数组的存取有点变态。我找了很多资料也不能自动创建某一类型的数组。既然不能自动，然后就使用半自动判断了，无非是if else之类的，看看这个属性是不是某一类型的数组。

下面是代码。

using System;
using System.Reflection;
using UnityEngine;
using System.Collections.Generic;
using System.Runtime.InteropServices;
public class ClassAnalyze<T>
{
    private string[] cols;

    public string[] Cols
    {
        get { return cols; }
        set { cols = value; }
    }
    private string[] values;

    public string[] Values
    {
        get { return values; }
        set { values = value; }
    }

    public string ClazzName
    {
        get { return tempClazz.GetType().Name; }

    }
    private PropertyInfo[] property;
    private T tempClazz;

    public static System.Object CreateObject(string objName) {
        return Assembly.GetExecutingAssembly().CreateInstance(objName);
    }
    public T GetClazz(string[] values)
    {//将数值赋给对象，然后再获取

        SetClazz(values);
        this.Values = values;
        if (tempClazz == null)
        {
            return default(T);
        }
        return tempClazz;
    }
    public void SetClazz(string[] values)
    {//将数值赋给对象，然后再获取

        if (tempClazz != null && this.Values.Length == values.Length)
        {
            this.Values = values;
            for (int i = 0; i < property.Length; i++)
            {
                if (tempClazz.GetType().GetProperty(Cols[i]).PropertyType.IsArray)
                {

                    var tempArr = StringToArr(tempClazz.GetType().GetProperty(Cols
[i]).GetValue(tempClazz, null), values[i].Split(new char[] { '|' }));

                    property[i].SetValue(tempClazz, tempArr, null);
                }
                else
                {
                    property[i].SetValue(tempClazz, Convert.ChangeType(values[i], property[i].PropertyType), null);
                }
            }
        }
    }
    private System.Object StringToArr(System.Object arr, string[] values)
    {
        if (arr is string[])
        {
            arr = new string[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as string[])[i] = values[i];
            }
            return (string[])arr;
        }
        else if (arr is int[])
        {
            arr = new int[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as int[])[i] = int.Parse(values[i]);
            }
            return (int[])arr;
        }
        else if (arr is Single[])
        {
            arr = new Single[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as Single[])[i] = Single.Parse(values[i]);
            }
            return (Single[])arr;
        }
        else if (arr is float[])
        {
            arr = new float[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as float[])[i] = float.Parse(values[i]);
            }
            return (float[])arr;
        }
        else if (arr is double[])
        {
            arr = new double[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as double[])[i] = double.Parse(values[i]);
            }
            return (double[])arr;
        }
        else if (arr is long[])
        {
            arr = new long[values.Length];
            for (int i = 0; i < values.Length; i++)
            {
                (arr as long[])[i] = long.Parse(values[i]);
            }
            return (long[])arr;
        }
        else if (arr is System.Object[])
        {
            arr = new System.Object[values.Length];

            for (int i = 0; i < values.Length; i++)
            {

                (arr as System.Object[])[i] = values[i];
            }
            return (System.Object[])arr;
        }


        return arr;
    }

    private string ArrToString(System.Object arr)
    {

        string values = "";


        if (arr is System.Object[])
        {
            foreach (var value in arr as System.Object[])
            {
                values += value + "|";
            }
        }
        else if (arr is string[])
        {
            foreach (var value in arr as string[])
            {
                values += value + "|";
            }
        }
        else if (arr is int[])
        {
            foreach (var value in arr as int[])
            {
                values += value + "|";
            }
        }
        else if (arr is Single[])
        {
            foreach (var value in arr as Single[])
            {
                values += value + "|";
            }
        }
        else if (arr is float[])
        {
            foreach (var value in arr as float[])
            {
                values += value + "|";
            }
        }
        else if (arr is double[])
        {
            foreach (var value in arr as double[])
            {
                values += value + "|";
            }
        }
        else if (arr is long[])
        {
            foreach (var value in arr as long[])
            {
                values += value + "|";
            }
        }

        values = values.TrimEnd(new char[] { '|' });
        return values;
    }
    public void AnalyzeClazz()
    {
        if (tempClazz != null)
        {

            property = tempClazz.GetType().GetProperties();
            Cols = new string[property.Length];
            Values = new string[property.Length];
            for (int i = 0; i < property.Length; i++)
            {
                Cols[i] = property[i].Name;
                string value = "";
                if (tempClazz.GetType().GetProperty(Cols[i]).PropertyType.IsArray)
                {
                    value = ArrToString(tempClazz.GetType().GetProperty(Cols[i]).GetValue(tempClazz, null));
                }
                else
                {
                    value = Convert.ToString(tempClazz.GetType().GetProperty(Cols[i]).GetValue(tempClazz, null));
                }
                Values[i] = value;
            }
        }
    }
    private ClassAnalyze()
    {

    }
    public ClassAnalyze(T tempClazz)
    {
        this.tempClazz = tempClazz;
        AnalyzeClazz();
    }

    public void Close()
    {
        tempClazz = default(T);
        Cols = null;
        Values = null;
        property = null;
    }
    public System.Object GetValue(T t, string colName)
    {
        return tempClazz.GetType().GetProperty(colName).GetValue(tempClazz, null);
    }
    public void SetValue(T t, string colName,string value)
    {
        for (int i = 0; i < property.Length; i++) {
            if (property[i].Name == colName) {
                if (property[i].PropertyType.IsArray)
                {
                    var tempArr = StringToArr(property[i].GetValue(tempClazz, null), value.Split(new char[] { '|' }));

                    property[i].SetValue(tempClazz, tempArr, null);
                }
                else {
                    property[i].SetValue(tempClazz, Convert.ChangeType(value, property[i].PropertyType), null);
                
                }
                break;
            }
        }

    }

    public override string ToString()
    {
        string values = "";
        for (int i = 0; i < Cols.Length; i++)
        {
            values += Cols[i] + ":{" + this.Values[i] + "} ";
        }

        return base.ToString() + ": " + values;
    }
}

　　

反射搞定后就是设计xml数据库了，具体的功能看个人需求。关于操作xml还是很简单的。

 

using System.Xml;
using System.Collections.Generic;
using System.IO;
using System;

using UnityEngine;
public abstract class DB
{
    /*public abstract bool CheckTable(string tableName);
    public abstract bool CheckDB(string dBName);
    public abstract void CreateTable(string tableName);
    public abstract void CreateDB(string dBName);*/
    public abstract bool Insert(string tableName, string[] cols, string[] values, string key);
    public abstract bool Update(string tableName, string[] cols, string[] values, string key);
    public abstract bool UpdateAll(string tableName);
    public abstract bool Delete(string tableName,  string key);
    public abstract bool DeleteAll(string tableName);
    public abstract string[] Select(string tableName, string key);
    public abstract List<string[]> SelectAll(string tableName);
    public abstract void Connect(string path);
    public abstract void Close();
    public abstract string[] SelectAllObjectsName(string tableName);
    
}
public class XmlSql : DB
{
    //public static string values[0] = "values[0]";
    private XmlDocument xmlDoc;
    private string path;
    private string rootName;
    public XmlSql()
    {
        xmlDoc = new XmlDocument();
    }
    public XmlSql(string path)
    {
        xmlDoc = new XmlDocument();
        Connect(path);
    }
    public override void Connect(string path)
    {
        if (xmlDoc == null) xmlDoc = new XmlDocument();
        if (!CheckDB(path))
        {
            this.path = path;
            rootName = path.Substring(path.LastIndexOf("/")+1,path.LastIndexOf(".")- path.LastIndexOf("/")-1);
            CreateDB(rootName);
        }
        else {
            this.path = path;
            
            xmlDoc.Load(this.path);
            rootName = xmlDoc.LastChild.LocalName;
        }
    }
    public override void Close()
    {
        if (xmlDoc != null)
        xmlDoc.Save(path);
        GC.Collect();
    }


    public XmlNode CheckTable(string tableName)
    {
        XmlNode root = xmlDoc.SelectSingleNode(rootName);
        if (root.SelectSingleNode(tableName) != null) {
            return root.SelectSingleNode(tableName);
        }

        return CreateTable(root,tableName);
    }
    public bool CheckDB(string dBName)
    {
        return File.Exists(dBName);
    }
    public XmlNode CreateTable(XmlNode root,string tableName)
    {
        XmlNode table = xmlDoc.CreateElement(tableName);
        root.AppendChild(table);
        xmlDoc.Save(path);
        return table;
    }
    public XmlNode CreateDB(string dBName)
    {
        File.CreateText(path).Close();
        XmlDeclaration xmlDeclaration = xmlDoc.CreateXmlDeclaration("1.0", "utf-8", null);
        XmlNode root = xmlDoc.CreateElement(dBName);
        xmlDoc.AppendChild(xmlDeclaration);
        xmlDoc.AppendChild(root);
        xmlDoc.Save(path);
        return root;
    }


    public override bool Insert(string tableName, string[] cols, string[] values,string key)
    {

        if (key == null || key == "") key = values[0];
        key = key.Replace(" ","");
        XmlNode table = CheckTable(tableName);

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象

        if (obj != null) {//待插入数据已经存在，插入失败
            return false;
        }

        XmlElement element = xmlDoc.CreateElement(key);

        for(int i=0;i<cols.Length;i++){
            XmlElement e = xmlDoc.CreateElement(cols[i]);
            e.InnerText = values[i].Replace(" ", "");
            element.AppendChild(e);
        }
        table.AppendChild(element);
        xmlDoc.Save(path);
        return true;
    }
    public override bool Update(string tableName, string[] cols, string[] values,string key)
    {
        if (key == null || key == "") key = values[0];
        key = key.Replace(" ", "");
        XmlNode table = CheckTable(tableName);

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象
        if (obj == null)
        {//待更新数据不存在，更新失败
            return false;
        }
        for (int i = 0; i < cols.Length; i++)
        {
            obj.SelectSingleNode(cols[i]).InnerText = values[i].Replace(" ", "");
        }
        xmlDoc.Save(path);
        return true;

       
    }

    public override bool UpdateAll(string tableName)
    {
        return false;
    }
    public override string[] Select(string tableName, string key)
    {
        XmlNode table = CheckTable(tableName);
        if (key == null || key == "") {
            if (table.ChildNodes.Count < 1) { 
            return null;
            }
            key = table.ChildNodes[0].LocalName;
        } 
        key = key.Replace(" ", "");
        
        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象

        if (obj == null) {
            return null;
        }

        string[] values = new string[obj.ChildNodes.Count];

        for (int i = 0; i < values.Length; i++) {
            values[i] = obj.ChildNodes.Item(i).InnerText.Replace(" ", "");
        }

        return values;
    }
    public override string[] SelectAllObjectsName(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        
        string[] values = new string[table.ChildNodes.Count];

        for (int i = 0; i < values.Length; i++) {
            values[i] = table.ChildNodes[i].LocalName;
        }
        return values;
    }
    public override List<string[]> SelectAll(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        if (table.ChildNodes.Count == 0) {
            return null;
        }
        List<string[]> elements = new List<string[]>();
        for(int i=0;i<table.ChildNodes.Count;i++){

            string[] values = new string[table.ChildNodes[i].ChildNodes.Count];
            for (int j = 0; j < table.ChildNodes[i].ChildNodes.Count; j++) {

                values[j] = table.ChildNodes[i].ChildNodes.Item(j).InnerText.Trim();
            }
            elements.Add(values);
        }
        return elements;
    }
    public override bool Delete(string tableName, string key)
    {
        XmlNode table = CheckTable(tableName);
        if (key == null || key == "") key = table.ChildNodes[0].LocalName;
        key = key.Replace(" ", "");
        

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象
        if (obj == null)
            return false;
        obj.RemoveAll();
        table.RemoveChild(obj);
        xmlDoc.Save(path);
        return true;
    }
    public override bool DeleteAll(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        table.RemoveAll();
        xmlDoc.Save(path);
        return true;
    }
}

接下来就是编辑器的设计。没什么高大上的东西，就是一些读写和调用的方法，以及一些逻辑上的处理。

 

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using System;
public class MyInspector : MonoBehaviour {

    //这个类是一个编辑器类，作用是展示存储的xml数据
    //选择对象，然后进行编辑
    //如果数据库中有这个数值，将其读取并显示
    //如果没有，则按需求创建数据
    //public string path;

    public string defaultKey = "PriKey";
    public ObjectMessage objMessage;
    public string DataPath = "gameData.xml";
    public MySql mySql;
    public bool IsHave = false;
    public bool IsShow = false;
    //private System.Object tempObj;
    public void GetDataBase(string dataPath) {
        DB db = MyDataBase.GetDataBase().Connection(dataPath);
        mySql = new MySql(db);
    }
    
    public void SaveMessage(string objName)
    {
        if (mySql != null)
        {
            System.Object obj = Assembly.GetExecutingAssembly().CreateInstance(objName);
            ClassAnalyze<System.Object> tempAnalyze = new ClassAnalyze<System.Object>(obj);
            obj=tempAnalyze.GetClazz(objMessage.values);

            if (IsHave)
            {
                mySql.Update(obj, defaultKey);

            }
            else {
                mySql.Insert(obj, defaultKey);
                ReadObj(objMessage.NamesOfModel[objMessage.indexOfModel]);
            }
               
        }
    }
    public void RemoveMessage(string objName, string key)
    {
        if (mySql != null)
        {
            System.Object obj = Assembly.GetExecutingAssembly().CreateInstance(objName);
            ClassAnalyze<System.Object> tempAnalyze = new ClassAnalyze<System.Object>(obj);
            tempAnalyze.SetValue(obj, defaultKey, key);

            if (IsHave)
            {
                mySql.Delete(obj, defaultKey);
                IsHave = false;
                ClearObjMessage();
            }
            
        }
    }
    
    public void ClearObjMessage()
    {
        for (int i = 0; i < objMessage.values.Length; i++) {
            objMessage.values[i] = "";
        }
    }
    
    public void ReadModel() {
        TextAsset[] tas = Resources.LoadAll<TextAsset>(objMessage.objectPath);
        objMessage. NamesOfModel = new string[tas.Length];
        for (int i = 0; i < tas.Length; i++) {
            objMessage.NamesOfModel[i] = tas[i].name;
        }
        
    }
    public void ReadObj(string tableName)
    {
        if(mySql!=null)
        objMessage.NamesOfObj = mySql.SelectAllObjectsName(tableName);
    }
    public void CheckData(string objName, string key)
    {
        System.Object obj = Assembly.GetExecutingAssembly().CreateInstance(objName);
        ClassAnalyze<System.Object> tempAnalyze = new ClassAnalyze<System.Object>(obj);
        tempAnalyze.SetValue(obj, defaultKey, key);
        objMessage.cols = tempAnalyze.Cols;
        obj = mySql.Select(obj, defaultKey);
        IsHave = (obj != null);
        if (IsHave)
        {
            tempAnalyze = new ClassAnalyze<System.Object>(obj);


            objMessage.values = tempAnalyze.Values;
        }
        else {
            objMessage.values = new string[objMessage.cols.Length];
        }
    }
}
[Serializable]
public class ObjectMessage
{

    public string objectPath = "Model";//对象所处的路径（基于Resources的相对路径）
    public string[] NamesOfModel;
    public string[] NamesOfObj;
    public int indexOfModel = 0;
    public int indexOfObj = 0;
    public string PriKey = "PriKey";
    public string[] cols;
    public string[] values;
    
}

下面这个脚本要放在Editor目录下面

using UnityEngine;
using System.Collections;
using UnityEditor;

[CustomEditor(typeof(MyInspector))]
public class EditorInspector : Editor {
    //重写展示面板


    //用户选择要加载的对象
    //提供一个主键，用户填写主键的值
    //默认主键是游戏对象名称
    //判断此对象是否已经保存在数据库中
    //如果已经存在此主键，则，加载数据到面板
    //如果没有此主键，提示用户是否创建
    //
    private SerializedObject TargetObj;
    private MyInspector MyPlane;
    private string[] shows= new string[]{"创建","加载"};
    private void InitPlane() {
        TargetObj = new SerializedObject(target);//获取编辑对象目标
        MyPlane = target as MyInspector;//转化为编辑对象
        CheckData();//检测数据
    }

    private void CheckData() {
        if (MyPlane.objMessage == null)//检查信息对象是否为空
        {
            MyPlane.objMessage = new ObjectMessage();//对象信息
        }
        if (MyPlane.objMessage.NamesOfModel == null || MyPlane.objMessage.NamesOfModel.Length < 1)
        {//检查对象数组
            MyPlane.ReadModel();//读取对象
        }
        if (MyPlane.objMessage.NamesOfObj == null || MyPlane.objMessage.NamesOfObj.Length < 1)
        {//检查对象数组
            MyPlane.ReadObj(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel]);//读取对象
        }
        if (MyPlane.objMessage.PriKey == null || MyPlane.objMessage.PriKey == "")
        {//检查对象主键名称
            //设置主键信息
            MyPlane.objMessage.PriKey = MyPlane.gameObject.name.Replace(" ", "");
        }
        if (MyPlane.mySql == null)
        {//检查数据库的连接状态
            //获取数据库连接
             MyPlane.GetDataBase(MyPlane.DataPath);
        }

    }
    void OnEnable() {

        InitPlane();
        
    }
    
    public override void OnInspectorGUI()
    {
        
        TargetObj.Update();//更新目标数据
        
        //主键值
        //CheckData();
        int lastModel = MyPlane.objMessage.indexOfModel;
        //对象选择列表
        MyPlane.objMessage.indexOfModel = EditorGUILayout.Popup("对象组", MyPlane.objMessage.indexOfModel, MyPlane.objMessage.NamesOfModel);
        
        if (lastModel != MyPlane.objMessage.indexOfModel) { //当改变对象时，更新主键值
            //更新主键值集合
            MyPlane.ReadObj(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel]);

        }
        int lastobj = MyPlane.objMessage.indexOfObj;
        if (MyPlane.objMessage.NamesOfObj.Length > 0)
        {
            MyPlane.objMessage.indexOfObj = EditorGUILayout.Popup("对象", MyPlane.objMessage.indexOfObj, MyPlane.objMessage.NamesOfObj);
        }
        if (lastobj != MyPlane.objMessage.indexOfObj || lastModel != MyPlane.objMessage.indexOfModel)
        { //主键值集合下标改变时
            //更新主键值
            if (MyPlane.objMessage.NamesOfObj.Length>0)
            MyPlane.objMessage.PriKey = MyPlane.objMessage.NamesOfObj[MyPlane.objMessage.indexOfObj];
        }
       

        string lastKey = MyPlane.objMessage.PriKey;
        //显示主键文本框
        MyPlane.objMessage.PriKey = EditorGUILayout.TextField("主键", MyPlane.objMessage.PriKey);
        //路径


        string lastPath = MyPlane.DataPath;
        MyPlane.DataPath = EditorGUILayout.TextField("数据路径",MyPlane.DataPath);
        
        //判断选择的对象列表
        //更新对象信息

        if (MyPlane.objMessage.indexOfModel != lastModel || lastKey != MyPlane.objMessage.PriKey || lastPath != MyPlane.DataPath || lastobj != MyPlane.objMessage.indexOfObj)//改变了一些数据时重新读取数据
        {
            MyPlane.IsHave = false;//标注数据改动

            CheckData();//读取数据前保证系统参数无误，以及各个对象正确加载

            MyPlane.CheckData(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel], MyPlane.objMessage.PriKey);
        }
        
        //当存在时直接加载
        //当不存在时，点击创建时加载

        
        bool _show = MyPlane.IsShow;//记录上一次的状态
        if (MyPlane.IsHave || (MyPlane.IsShow = EditorGUILayout.Foldout(MyPlane.IsShow, shows[MyPlane.IsShow ? 1 : 0])))
        {
            if (!_show && !MyPlane.IsHave)//数据不存在而且点击了创建的时候
            { //仅执行一次，保证数据不被一直刷新而导致的无法读写
                //当数据不存在，而且点击创建时  清除信息

                MyPlane.ClearObjMessage();//清除数据的缓存
            }
        }
        //也要只进行一次的读写，保证可以进行修改操作
        if (MyPlane.IsHave || MyPlane.IsShow)//当数据存在或者点击创建时加载数据
        {
            for (int i = 0; i < MyPlane.objMessage.cols.Length; i++)
            {
                if (MyPlane.defaultKey == MyPlane.objMessage.cols[i]) {
                    MyPlane.objMessage.values[i] = MyPlane.objMessage.PriKey;
                    continue;
                }
                MyPlane.objMessage.values[i] = EditorGUILayout.TextField(MyPlane.objMessage.cols[i], MyPlane.objMessage.values[i]);

            }
            if (GUILayout.Button("Save"))
            {
                MyPlane.SaveMessage(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel]);
            }

            if (MyPlane.IsHave&& GUILayout.Button("Remove"))
            {
                MyPlane.RemoveMessage(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel], MyPlane.objMessage.PriKey);
                MyPlane.ReadObj(MyPlane.objMessage.NamesOfModel[MyPlane.objMessage.indexOfModel]);
                
            }
        }

        
        
        TargetObj.ApplyModifiedProperties();
        
    }

    void show(System.Object message) {
        Debug.Log(message);
    }
}

新的xml数据存储格式：新建脚本MyXmlSql，继承DB，然后实现具体的方法：

using System.Xml;
using System.Collections.Generic;
using System.IO;
using System;

public class MyXmlSql : DB
{
    private XmlDocument xmlDoc;
    private string path;
    private string rootName;
    public MyXmlSql()
    {
        xmlDoc = new XmlDocument();
    }
    public MyXmlSql(string path)
    {
        xmlDoc = new XmlDocument();
        Connect(path);
    }
    public override void Connect(string path)
    {
        if (xmlDoc == null) xmlDoc = new XmlDocument();
        if (!CheckDB(path))
        {
            this.path = path;
            rootName = path.Substring(path.LastIndexOf("/")+1,path.LastIndexOf(".")- path.LastIndexOf("/")-1);
            CreateDB(rootName);
        }
        else {
            this.path = path;
            
            xmlDoc.Load(this.path);
            rootName = xmlDoc.LastChild.LocalName;
        }
    }
    public override void Close()
    {
        if (xmlDoc != null)
        xmlDoc.Save(path);
        GC.Collect();
    }


    public XmlNode CheckTable(string tableName)
    {
        XmlNode root = xmlDoc.SelectSingleNode(rootName);
        if (root.SelectSingleNode(tableName) != null) {
            return root.SelectSingleNode(tableName);
        }

        return CreateTable(root,tableName);
    }
    public bool CheckDB(string dBName)
    {
        return File.Exists(dBName);
    }
    public XmlNode CreateTable(XmlNode root,string tableName)
    {
        XmlNode table = xmlDoc.CreateElement(tableName);
        root.AppendChild(table);
        xmlDoc.Save(path);
        return table;
    }
    public XmlNode CreateDB(string dBName)
    {
        File.CreateText(path).Close();
        XmlDeclaration xmlDeclaration = xmlDoc.CreateXmlDeclaration("1.0", "utf-8", null);
        XmlNode root = xmlDoc.CreateElement(dBName);
        xmlDoc.AppendChild(xmlDeclaration);
        xmlDoc.AppendChild(root);
        xmlDoc.Save(path);
        return root;
    }


    public override bool Insert(string tableName, string[] cols, string[] values,string key)
    {

        if (key == null || key == "") key = values[0];
        key = key.Replace(" ","");
        XmlNode table = CheckTable(tableName);

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象

        if (obj != null) {//待插入数据已经存在，插入失败
            return false;
        }

        XmlElement element = xmlDoc.CreateElement(key);

        
        for (int i = 0; i < cols.Length; i++) {
            XmlAttribute xa = xmlDoc.CreateAttribute(cols[i]);

            xa.Value = values[i].Replace(" ", "");
            element.Attributes.Append(xa);
            
        }

        
        table.AppendChild(element);
        xmlDoc.Save(path);
        return true;
    }
    public override bool Update(string tableName, string[] cols, string[] values,string key)
    {
        if (key == null || key == "") key = values[0];
        key = key.Replace(" ", "");
        XmlNode table = CheckTable(tableName);

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象
        if (obj == null)
        {//待更新数据不存在，更新失败
            return false;
        }
        for (int i = 0; i < cols.Length; i++)
        {
            obj.Attributes[cols[i]].Value = values[i].Replace(" ", "");

        }
        xmlDoc.Save(path);
        return true;

       
    }

    public override bool UpdateAll(string tableName)
    {
        return false;
    }
    public override string[] Select(string tableName, string key)
    {
        XmlNode table = CheckTable(tableName);
        if (key == null || key == "") {
            if (table.ChildNodes.Count < 1) { 
            return null;
            }
            key = table.ChildNodes[0].LocalName;
        } 
        key = key.Replace(" ", "");
        
        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象

        if (obj == null) {
            return null;
        }

        string[] values = new string[obj.Attributes.Count]; 

for (int i = 0; i < values.Length; i++) {
            values[i] = obj.Attributes[i].Value.Replace(" ", "");
        }

        return values;
    }
    public override string[] SelectAllObjectsName(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        
        string[] values = new string[table.ChildNodes.Count];

        for (int i = 0; i < values.Length; i++) {
            values[i] = table.ChildNodes[i].LocalName;
        }
        return values;
    }
    public override List<string[]> SelectAll(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        if (table.ChildNodes.Count == 0) {
            return null;
        }
        List<string[]> elements = new List<string[]>();
        for(int i=0;i<table.ChildNodes.Count;i++){//遍历表的子节点
            string[] values = new string[table.ChildNodes[i].Attributes.Count];
            for (int j = 0; j < table.ChildNodes[i].Attributes.Count; j++)
            {
                values[j] = table.ChildNodes[i].Attributes[j].Value.Trim();
            }
            elements.Add(values);
        }
        return elements;
    }
    public override bool Delete(string tableName, string key)
    {
        XmlNode table = CheckTable(tableName);
        if (key == null || key == "") key = table.ChildNodes[0].LocalName;
        key = key.Replace(" ", "");
        

        XmlNode obj = table.SelectSingleNode(key);//按照key值确定元素对象
        if (obj == null)
            return false;
        obj.RemoveAll();
        table.RemoveChild(obj);
        xmlDoc.Save(path);
        return true;
    }
    public override bool DeleteAll(string tableName)
    {
        XmlNode table = CheckTable(tableName);
        table.RemoveAll();
        xmlDoc.Save(path);
        return true;
    }
    
}

 本文地址：http://www.cnblogs.com/jqg-aliang/p/4767026.html