Unity3d- 资源

Data与Resources文件夹
一般只读文件放到Resources目录
Data用于新建的文件或者要修改的文件
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Unity默认的Resource加载
　　保存和读取资源的 最简单的 方式了。但是 如果想让资源在编译后不改变，只能这样做。
　　因为这里面的内容会 组合并编译到resource.assets文件（此文件可以在编译过的游戏的Data文件中找到）
　　可以从编译过的项目文件Resource.assets中去加载

用法
　　//Texture2D  （Texture2D）Resouce.Load(fileName);
　　//文本资源      （TextAsset)Resouce.Load("ddd");
　　                     读取文本内容  TestAsset.text
　　//声音             (AudioClip)Resouce.Load();

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加载编译之后的文件

using System.IO;
using UnityEngine;
using System.Collections;

public class temp : MonoBehaviour
{
    private string fileName = "a.jpg";
    private string url;
    private Texture2D externalImage;
    // Use this for initialization
    void Start()
    {
        url = "file:" + Application.dataPath;
        url = Path.Combine(url, "Resources");
        url = Path.Combine(url, fileName);

        StartCoroutine(LoadWWW());
    }

    private IEnumerator LoadWWW()
    {
        yield return 0;
        WWW www=new WWW(url);
        yield return www;
        externalImage = www.texture;
    }
    // Update is called once per frame
    void Update()
    {

    }
}

需要System.IO类
www类的对象时以“file:"开头的URL，
使用Path.Combine()而不是 ”\   /“以避免跨平台的问题

WWW和资源内容
WWW类定义了几个不同的属性和方法 用于把下载的资源 文件 数据提取到变量中
.text 只读 web数据作为string类型返回
.texture 只读 作为Texture2D类型返回
.GetAudioClip() 方法 作为AudioClip对象类型返回

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通过从互联网 下载文件与加载外部资源文件
从服务器下载

using UnityEngine;
using System.Collections;

public class temp : MonoBehaviour
{
    private string url="http://www.packtpub.com/sites/default/files/packt_logo.png";
    private Texture2D externalImage;
    // Use this for initialization
    void Start()
    {
        StartCoroutine(LoadWWW());
    }

    private void OnGUI()
    {
        GUILayout.Label("url="+url);
        GUILayout.Label(externalImage);
    }
    private IEnumerator LoadWWW()
    {
        yield return 0;
        WWW imageFile=new WWW(url);
        yield return imageFile;
        externalImage = imageFile.texture;
    }
    // Update is called once per frame
    void Update()
    {

    }
}

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使用外部文本文件和XML数据
最简单的是TextAsset 共有变量（编译后数据文件不再改变的情况下适用）

 public TextAsset DataTestAsset;
    private string textData;

    void Start()
    {
        textData = DataTestAsset.text;
    }

C#文件流加载外部文本文件

using System;
using UnityEngine;
using System.Collections;
using System.IO;
public class FileReadWriteManager
{
    public void WriteTextFile(string pathAndName, string stringData)
    {
        //remove file ,if exists
        FileInfo textFile=new FileInfo(pathAndName);
        if (textFile.Exists)
        {
            textFile.Delete();
        }
        //create new empty file
        StreamWriter writer;
        writer = textFile.CreateText();
        //write text to file
        writer.Write(stringData);
        writer.Close();
    }

    public string ReadTextFile(string pathAndName)
    {
        string dataAsString = "";
        try
        {
            //open text file
            StreamReader textReader = File.OpenText(pathAndName);
            //read content
            dataAsString = textReader.ReadToEnd();
            textReader.Close();
        }
        catch (Exception e)
        {
            
        }
        return dataAsString;
    }
}

调用示例

private string fileName = "cities.txt";
    private string filePath = "";
    private FileReadWriteManager fileReadWriteManager=new FileReadWriteManager();
    void Start()
    {
        filePath = Path.Combine(Application.dataPath, "Resources");
        filePath = Path.Combine(filePath, fileName);
        string textContent = fileReadWriteManager.ReadTextFile(filePath);
    }

 private string fileName = "hello.txt";
    private string foleName = "Data";
    //需要在Project面板中创建一个Data目录文件夹
    private string filePath = "";
    private FileReadWriteManager fileReadWriteManager=new FileReadWriteManager();
    void Start()
    {
        filePath = Application.dataPath + Path.DirectorySeparatorChar + fileName;
        string textData = "abc\n def";

        fileReadWriteManager.WriteTextFile(filePath, textData);
        filePath = Path.Combine(filePath, fileName);
        string textContent = fileReadWriteManager.ReadTextFile(filePath);
    }