Unity 读取与修改Json

一、读取

Unity读取Json算是一个很常用的功能，今天来小小的总结一下。

首先你得写个json，百度Json可以找到很多接送工具。

比如我写的json，注意：因为有中文，所以要保存UTF-8的格式。后缀名可以为.txt 也可以为.json

第一种，JsonData读取的方式，这种方法比较直接，先把数据拿过来再处理

        StreamReader streamreader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");   //读取数据，转换成数据流
        JsonReader jsonReader = new JsonReader(streamreader);                                               //转换成json数据
        JsonData jsonData = JsonMapper.ToObject(jsonReader);                                                //转化为jsonData
        for (int i = 0; i < jsonData[0][0].Count; i++)
        {
            Debug.Log(jsonData[0][i]["id"] + "    " + jsonData[0][i]["name"] + "    " + jsonData[0][i]["age"]);
        }

运行结果

第二种，先写好接收Json的类，再用类的实例去接收，这种开始要蛮烦一点，但后面用起来就比较有条理

定义json数据的类

public class PlayerInfo {
    public string id;
    public string name;
    public int age;
}

public class Root
{
    public List<PlayerInfo> sites;
}

读取json

        StreamReader streamreader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");   //读取数据，转换成数据流
        JsonReader jsonReader = new JsonReader(streamreader);                                               //转换成json数据
        Root root = JsonMapper.ToObject<Root>(jsonReader);                                                //转化为jsonData
        Debug.Log(root.sites.Count);
        for (int i = 0; i < root.sites.Count; i++)
        {
            Debug.Log(root.sites[i].id + "    " + root.sites[i].name + "    " + root.sites[i].age);
        }

另外，JsonMapper的ToObject方法可以读取三种类容JsonReader、TextReader和String，上面用的读是JsonReader的方法

        public static JsonData ToObject(JsonReader reader);
        public static JsonData ToObject(TextReader reader);
        public static JsonData ToObject(string json);
        public static T ToObject<T>(JsonReader reader);
        public static T ToObject<T>(TextReader reader);
        public static T ToObject<T>(string json);

来看看string读取（1）路径加载文本

        //StreamReader streamreader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");   //读取数据，转换成数据流
        //JsonReader jsonReader = new JsonReader(streamreader);                                               //转换成json数据
        string jsonStr = File.ReadAllText(Application.dataPath + "/StreamingAssets/Test.txt");                //读取数据，转换成数string
        Root root = JsonMapper.ToObject<Root>(jsonStr);                                                //转化为jsonData
        Debug.Log(root.sites.Count);
        for (int i = 0; i < root.sites.Count; i++)
        {
            Debug.Log(root.sites[i].id + "    " + root.sites[i].name + "    " + root.sites[i].age);
        }

string读取（2）Resource加载文本

        //StreamReader streamreader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");   //读取数据，转换成数据流
        //JsonReader jsonReader = new JsonReader(streamreader);                                               //转换成json数据
        //string jsonStr = File.ReadAllText(Application.dataPath + "/StreamingAssets/Test.txt");              //读取数据，转换成数string
        TextAsset textAsset = Resources.Load("Test") as TextAsset;
        string jsonStr = textAsset.text;
        Root root = JsonMapper.ToObject<Root>(jsonStr);                                                //转化为jsonData
        Debug.Log(root.sites.Count);
        for (int i = 0; i < root.sites.Count; i++)
        {
            Debug.Log(root.sites[i].id + "    " + root.sites[i].name + "    " + root.sites[i].age);
        }

TextReader读取

        //StreamReader streamreader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");   //读取数据，转换成数据流
        //JsonReader jsonReader = new JsonReader(streamreader);                                               //转换成json数据
        //string jsonStr = File.ReadAllText(Application.dataPath + "/StreamingAssets/Test.txt");              //读取数据，转换成数string
        //TextAsset textAsset = Resources.Load("Test") as TextAsset;
        //string jsonStr = textAsset.text;
        TextReader textReader = new StreamReader(Application.dataPath + "/StreamingAssets/Test.txt");
        Root root = JsonMapper.ToObject<Root>(textReader);                                                //转化为jsonData
        Debug.Log(root.sites.Count);
        for (int i = 0; i < root.sites.Count; i++)
        {
            Debug.Log(root.sites[i].id + "    " + root.sites[i].name + "    " + root.sites[i].age);
        }

二、修改

    /// <summary>
    /// 修改Json文本
    /// </summary>
    /// <param name="url">json的路径</param>
    /// <param name="str">要修改的json内容</param>
    public static void SaveVer(string url, string str)
    {
        StreamWriter sw = new StreamWriter(url);
        sw.Write(str);
        sw.Close();
        AssetDatabase.Refresh();
    }