如何在 Json.NET 中将巨大的 JSON 文件解析为流

I have a very, very large JSON file (1000+ MB) of identical JSON objects. For example:

[
    {
        "id": 1,
        "value": "hello",
        "another_value": "world",
        "value_obj": {
            "name": "obj1"
        },
        "value_list": [
            1,
            2,
            3
        ]
    },
    {
        "id": 2,
        "value": "foo",
        "another_value": "bar",
        "value_obj": {
            "name": "obj2"
        },
        "value_list": [
            4,
            5,
            6
        ]
    },
    {
        "id": 3,
        "value": "a",
        "another_value": "b",
        "value_obj": {
            "name": "obj3"
        },
        "value_list": [
            7,
            8,
            9
        ]

    },
    ...
]

Every single item in the root JSON list follows the same structure and thus would be individually deserializable. I already have the C# classes written to receive this data, and deserializing a JSON file containing a single object without the list works as expected.

At first, I tried to just directly deserialize my objects in a loop:

JsonSerializer serializer = new JsonSerializer();
MyObject o;
using (FileStream s = File.Open("bigfile.json", FileMode.Open))
using (StreamReader sr = new StreamReader(s))
using (JsonReader reader = new JsonTextReader(sr))
{
    while (!sr.EndOfStream)
    {
        o = serializer.Deserialize<MyObject>(reader);
    }
}

这不起作用，抛出了一个异常，清楚地声明需要的是对象，而不是列表.我的理解是，此命令将只读取JSON文件根级别包含的单个对象，但由于我们有list个对象，因此这是一个无效请求.

My next idea was to deserialize as a C# List of objects:

JsonSerializer serializer = new JsonSerializer();
List<MyObject> o;
using (FileStream s = File.Open("bigfile.json", FileMode.Open))
using (StreamReader sr = new StreamReader(s))
using (JsonReader reader = new JsonTextReader(sr))
{
    while (!sr.EndOfStream)
    {
        o = serializer.Deserialize<List<MyObject>>(reader);
    }
}

This does succeed. However, it only somewhat reduces the issue of high RAM usage. In this case it does look like the application is deserializing items one at a time, and so is not reading the entire JSON file into RAM, but we still end up with a lot of RAM usage because the C# List object now contains all of the data from the JSON file in RAM. This has only displaced the problem.

然后，我决定在进入循环之前，通过执行sr.Read()，简单地try 从流的开头删除一个字符(以消除[个字符).然后，第一个对象确实读取成功，但后续对象没有成功，只有"意外令牌"例外.我猜这是逗号和对象之间的空格，这会让读者产生反感.

简单地删除方括号是行不通的，因为对象确实包含它们自己的基本列表，正如您在示例中看到的那样.即使try 使用},作为分隔符也行不通，因为正如您所看到的，对象中存在子对象.

我的目标是，能够从流中一次读取一个对象.读取一个对象，对其进行处理，然后从RAM中丢弃它，然后读取下一个对象，依此类推.这将消除将整个JSON字符串或数据的全部内容作为C#对象加载到RAM中的需要.

我遗漏了什么？