ThreadStatic特性 ThreadStatic特性

文章：ThreadStatic特性

地址：https://www.cnblogs.com/xuejietong/p/10997385.html

带有threadStaticAttribute标记的静态字段在线程之间不共享。每个执行线程都有一个单独的字段实例，并独立地设置和获取该字段的值。

如果在不同的线程上访问该字段，则它将包含不同的值。除了将threadStaticAttribute属性应用于字段之外，还必须将其定义为静态字段（在C中）或共享字段（在Visual Basic中）。不要为标记为threadStaticAttribute的字段指定初始值，因为此类初始化仅在类构造函数执行时发生一次（静态构造函数），因此只影响一个线程。

研究农业银行的支付接口demo时，发现代码中使用了这个特性：

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;

namespace com.abc.trustpay.client
{
    public class JSON
    {
        [ThreadStatic]
        private static string iJsonString = "";

        public static void setJsonString(string aJsonString)
        {
            JSON.iJsonString = aJsonString.Trim();
        }

        public static string WriteDictionary(IDictionary dic)
        {
            StringBuilder stringBuilder = new StringBuilder("");
            bool flag = false;
            stringBuilder.Append("{");
            foreach (DictionaryEntry dictionaryEntry in dic)
            {
                if (flag)
                {
                    stringBuilder.Append(",");
                }
                stringBuilder.Append("\"");
                stringBuilder.Append(dictionaryEntry.Key);
                stringBuilder.Append("\":");
                stringBuilder.Append("\"");
                stringBuilder.Append(dictionaryEntry.Value);
                stringBuilder.Append("\"");
                flag = true;
            }
            return stringBuilder.ToString();
        }

        public static string WriteDictionarys(IDictionary dic)
        {
            StringBuilder stringBuilder = new StringBuilder("");
            bool flag = false;
            stringBuilder.Append("[");
            foreach (int num in dic.Keys)
            {
                if (flag)
                {
                    stringBuilder.Append("},");
                }
                string value = JSON.WriteDictionary((IDictionary)dic[num]);
                stringBuilder.Append(value);
                flag = true;
            }
            stringBuilder.Append("}]");
            return stringBuilder.ToString();
        }

        public static string GetKeyValue(string aTag)
        {
            string text = JSON.iJsonString;
            int num = text.IndexOf(aTag);
            string result;
            if (num == -1)
            {
                result = "";
            }
            else
            {
                while (!text.Substring(num - 1, 1).Equals("\"") || !text.Substring(num + aTag.Length, 1).Equals("\""))
                {
                    num = text.IndexOf(aTag, num + 1);
                    if (num == -1)
                    {
                        result = "";
                        return result;
                    }
                }
                int length = aTag.Length;
                num = num + length + 2;
                string text2 = "";
                char c = text[num];
                if (c == '{')
                {
                    text2 = JSON.GetObjectValue(num, aTag, text);
                }
                if (c == '"')
                {
                    text2 = JSON.GetStringValue(num, aTag, text);
                }
                result = text2;
            }
            return result;
        }

        private static string GetObjectValue(int index, string aTag, string json)
        {
            int num = 0;
            StringBuilder stringBuilder = new StringBuilder();
            char c;
            while (true)
            {
                c = json[index];
                if (c == '{')
                {
                    num++;
                }
                if (c == '}')
                {
                    num--;
                }
                if (num == 0)
                {
                    break;
                }
                stringBuilder.Append(c);
                index++;
            }
            stringBuilder.Append(c);
            return stringBuilder.ToString();
        }

        private static string GetStringValue(int index, string aTag, string json)
        {
            StringBuilder stringBuilder = new StringBuilder();
            index++;
            while (true)
            {
                char c = json[index++];
                if (c == '"')
                {
                    break;
                }
                stringBuilder.Append(c);
            }
            return stringBuilder.ToString();
        }

        public static Dictionary<int, Hashtable> GetArrayValue(string aTag)
        {
            string text = JSON.iJsonString;
            Dictionary<int, Hashtable> dictionary = new Dictionary<int, Hashtable>();
            Hashtable hashtable = new Hashtable();
            StringBuilder stringBuilder = new StringBuilder();
            int num = text.IndexOf(aTag);
            Dictionary<int, Hashtable> result;
            if (num == -1)
            {
                result = dictionary;
            }
            else
            {
                int length = aTag.Length;
                num = num + length + 2;
                int num2 = 0;
                while (true)
                {
                    char c = text[num++];
                    if (c != '[')
                    {
                        if (c != ']')
                        {
                            stringBuilder.Append(c);
                        }
                        if (c == '}')
                        {
                            c = text[num++];
                            hashtable.Add(num2, stringBuilder);
                            num2++;
                            stringBuilder = new StringBuilder();
                        }
                        if (c == ']')
                        {
                            break;
                        }
                    }
                }
                if (hashtable.Count == 0)
                {
                    result = dictionary;
                }
                else
                {
                    dictionary = JSON.ParseArray(hashtable);
                    result = dictionary;
                }
            }
            return result;
        }

        public static Dictionary<int, Hashtable> ParseArray(Hashtable hts)
        {
            Dictionary<int, Hashtable> dictionary = new Dictionary<int, Hashtable>();
            Hashtable value = new Hashtable();
            foreach (int num in hts.Keys)
            {
                string json = hts[num].ToString();
                value = JSON.ParseString(json);
                dictionary.Add(num, value);
                value = new Hashtable();
            }
            return dictionary;
        }

        public static Hashtable ParseString(string json)
        {
            StringBuilder stringBuilder = new StringBuilder();
            Hashtable hashtable = new Hashtable();
            int num = json.IndexOf("{");
            int length = json.Length;
            json = json.Substring(num + 1, length - 2);
            json = json.Replace("\"", "");
            string[] array = json.Split(new char[]
            {
                ','
            });
            string[] array2 = new string[2];
            for (int i = 0; i < array.Length; i++)
            {
                array2 = array[i].Split(new char[]
                {
                    ':'
                });
                hashtable.Add(array2[0], array2[1]);
            }
            return hashtable;
        }
    }
}