internal static class StringBuilderCache{

    private const int MAX_BUILDER_SIZE = 360;

    [ThreadStatic]
    private static StringBuilder CachedInstance;

    public static StringBuilder Acquire(int capacity = StringBuilder.DefaultCapacity){
        if(capacity <= MAX_BUILDER_SIZE){
            StringBuilder sb = StringBuilderCache.CachedInstance;
            if (sb != null){
                if(capacity <= sb.Capacity){
                    StringBuilderCache.CachedInstance = null;
                    sb.Clear();
                    return sb;
                }
            }
        }
        return new StringBuilder(capacity);
    }

    public static void Release(StringBuilder sb){
        if (sb.Capacity <= MAX_BUILDER_SIZE){
            StringBuilderCache.CachedInstance = sb;
        }
    }

    public static string GetStringAndRelease(StringBuilder sb){
        string result = sb.ToString();
        Release(sb);
        return result;
    }
}

(转载)线程静态在对象缓存中的妙用,布布扣,bubuko.com

(转载)线程静态在对象缓存中的妙用